Why do I get badly formatted numerical results when I use StringForm? The 2019 Stack Overflow...

How can I create a character who can assume the widest possible range of creature sizes?

Is three citations per paragraph excessive for undergraduate research paper?

What do hard-Brexiteers want with respect to the Irish border?

Why can Shazam do this?

Inflated grade on resume at previous job, might former employer tell new employer?

Why do I get badly formatted numerical results when I use StringForm?

Why isn't airport relocation done gradually?

Are there any other methods to apply to solving simultaneous equations?

Where does the "burst of radiance" from Holy Weapon originate?

Limit to 0 ambiguity

Springs with some finite mass

Limit the amount of RAM Mathematica may access?

Is "plugging out" electronic devices an American expression?

Could a US political party gain complete control over the government by removing checks & balances?

How to manage monthly salary

What is the steepest angle that a canal can be traversable without locks?

How to reverse every other sublist of a list?

What could be the right powersource for 15 seconds lifespan disposable giant chainsaw?

Why is my p-value correlated to difference between means in two sample tests?

Idiomatic way to prevent slicing?

How to change the limits of integration

Lethal sonic weapons

Manuscript was "unsubmitted" because the manuscript was deposited in Arxiv Preprints

What does "sndry explns" mean in one of the Hitchhiker's guide books?



Why do I get badly formatted numerical results when I use StringForm?



The 2019 Stack Overflow Developer Survey Results Are InHow to increase the font size when printing?Is it possible to change the fontsize and simultaneously TabSpacing when printing a notebook in the working enviromentHow to Print a Cell Landscape in a Portrait Orientation Notebook?How can one programatically change Magnification or select others than offered?Printing problem: PDF output has a plot errorStop notebook from auto-scrolling upon printing












2












$begingroup$


The following example prints the square and cube of numbers from 0.5 to 6



Do[
Print[StringForm["the square of `` is ``, the cube of it is ``", i, i^2, i^3]],
{i, 0.5, 6, 0.1}]


It should be fine, however, for 0.7 Mathematica prints




the square of 0.7` is 0.48999999999999994`, the cube of it is 0.3429999999999999`



Why is the square of 0.7 approximated by 0.48999999999999994? No approximation will be made if I did not use StringForm, why is that?



By the way, there is a ` at the end of each output number, why is it there?










share|improve this question











$endgroup$

















    2












    $begingroup$


    The following example prints the square and cube of numbers from 0.5 to 6



    Do[
    Print[StringForm["the square of `` is ``, the cube of it is ``", i, i^2, i^3]],
    {i, 0.5, 6, 0.1}]


    It should be fine, however, for 0.7 Mathematica prints




    the square of 0.7` is 0.48999999999999994`, the cube of it is 0.3429999999999999`



    Why is the square of 0.7 approximated by 0.48999999999999994? No approximation will be made if I did not use StringForm, why is that?



    By the way, there is a ` at the end of each output number, why is it there?










    share|improve this question











    $endgroup$















      2












      2








      2





      $begingroup$


      The following example prints the square and cube of numbers from 0.5 to 6



      Do[
      Print[StringForm["the square of `` is ``, the cube of it is ``", i, i^2, i^3]],
      {i, 0.5, 6, 0.1}]


      It should be fine, however, for 0.7 Mathematica prints




      the square of 0.7` is 0.48999999999999994`, the cube of it is 0.3429999999999999`



      Why is the square of 0.7 approximated by 0.48999999999999994? No approximation will be made if I did not use StringForm, why is that?



      By the way, there is a ` at the end of each output number, why is it there?










      share|improve this question











      $endgroup$




      The following example prints the square and cube of numbers from 0.5 to 6



      Do[
      Print[StringForm["the square of `` is ``, the cube of it is ``", i, i^2, i^3]],
      {i, 0.5, 6, 0.1}]


      It should be fine, however, for 0.7 Mathematica prints




      the square of 0.7` is 0.48999999999999994`, the cube of it is 0.3429999999999999`



      Why is the square of 0.7 approximated by 0.48999999999999994? No approximation will be made if I did not use StringForm, why is that?



      By the way, there is a ` at the end of each output number, why is it there?







      output-formatting number-form






      share|improve this question















      share|improve this question













      share|improve this question




      share|improve this question








      edited 7 mins ago









      m_goldberg

      88.4k872199




      88.4k872199










      asked 7 hours ago









      zyyzyy

      1236




      1236






















          2 Answers
          2






          active

          oldest

          votes


















          5












          $begingroup$

          This is what happens when you use IEEE-754 double-precision math instead of exact math.



          StringForm, InputForm, FullForm etc. give you all possible digits of these IEEE-754 double-precision numbers used internally. This is no different from any other programming language.



          Other number display functions, like NumberForm, show fewer digits. The internal representation of the number doesn't change though.



          The backtick ` indicates a machine-precision number, which is usually (always?) an IEEE-754 double-precision number.



          You can get the result you're looking for by doing the conversion to numerical values after the squaring/cubing:



          Do[Print[StringForm["the square of `` is ``, the cube of it is ``", 
          N[i], N[i^2], N[i^3]]], {i, 1/2, 6, 1/10}]



          the square of 0.7` is 0.49`, the cube of it is 0.343`







          share|improve this answer











          $endgroup$





















            1












            $begingroup$

            StringForm is very old. It goes all the back to V1.0, released in 1988. It represents an attempt by WRI to have an IO formatter that would appeal to programmers familiar with C and similar programming languages.



            V6.0, released in 2003, added formatting tools that are not only easier to use but which are better integrated into Mathematica's way of doing things. One of the new IO formatters was Row. It does not have the problem with formatting machine numbers that you ran into by using StringForm.



            Here is how you can get your output with Row.



            Column[
            Table[
            Row[{"the square of ", i, " is ", i^2, ", the cube of it is ", i^3}],
            {i, 0.5, 1., .1}]]


            output



            One of the nice features of the newer IO formatting tools is that they allow styles to be applied at almost any level. For example:



            numStyle[num_?NumericQ] := Style[num, Red, Bold, Italic]
            Style[
            Column[
            Table[
            Row[
            {"the square of ", numStyle[i], " is ", numStyle[i^2],
            ", the cube of it is ", numStyle[i^3]}],
            {i, 0.5, 1., .1}]],
            FontFamily -> "Arial"]


            styled



            It isn't that you can't apply styles to StringForm output, but that it is harder to do and requires more care.






            share|improve this answer











            $endgroup$














              Your Answer





              StackExchange.ifUsing("editor", function () {
              return StackExchange.using("mathjaxEditing", function () {
              StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
              StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
              });
              });
              }, "mathjax-editing");

              StackExchange.ready(function() {
              var channelOptions = {
              tags: "".split(" "),
              id: "387"
              };
              initTagRenderer("".split(" "), "".split(" "), channelOptions);

              StackExchange.using("externalEditor", function() {
              // Have to fire editor after snippets, if snippets enabled
              if (StackExchange.settings.snippets.snippetsEnabled) {
              StackExchange.using("snippets", function() {
              createEditor();
              });
              }
              else {
              createEditor();
              }
              });

              function createEditor() {
              StackExchange.prepareEditor({
              heartbeatType: 'answer',
              autoActivateHeartbeat: false,
              convertImagesToLinks: false,
              noModals: true,
              showLowRepImageUploadWarning: true,
              reputationToPostImages: null,
              bindNavPrevention: true,
              postfix: "",
              imageUploader: {
              brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
              contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
              allowUrls: true
              },
              onDemand: true,
              discardSelector: ".discard-answer"
              ,immediatelyShowMarkdownHelp:true
              });


              }
              });














              draft saved

              draft discarded


















              StackExchange.ready(
              function () {
              StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmathematica.stackexchange.com%2fquestions%2f194909%2fwhy-do-i-get-badly-formatted-numerical-results-when-i-use-stringform%23new-answer', 'question_page');
              }
              );

              Post as a guest















              Required, but never shown

























              2 Answers
              2






              active

              oldest

              votes








              2 Answers
              2






              active

              oldest

              votes









              active

              oldest

              votes






              active

              oldest

              votes









              5












              $begingroup$

              This is what happens when you use IEEE-754 double-precision math instead of exact math.



              StringForm, InputForm, FullForm etc. give you all possible digits of these IEEE-754 double-precision numbers used internally. This is no different from any other programming language.



              Other number display functions, like NumberForm, show fewer digits. The internal representation of the number doesn't change though.



              The backtick ` indicates a machine-precision number, which is usually (always?) an IEEE-754 double-precision number.



              You can get the result you're looking for by doing the conversion to numerical values after the squaring/cubing:



              Do[Print[StringForm["the square of `` is ``, the cube of it is ``", 
              N[i], N[i^2], N[i^3]]], {i, 1/2, 6, 1/10}]



              the square of 0.7` is 0.49`, the cube of it is 0.343`







              share|improve this answer











              $endgroup$


















                5












                $begingroup$

                This is what happens when you use IEEE-754 double-precision math instead of exact math.



                StringForm, InputForm, FullForm etc. give you all possible digits of these IEEE-754 double-precision numbers used internally. This is no different from any other programming language.



                Other number display functions, like NumberForm, show fewer digits. The internal representation of the number doesn't change though.



                The backtick ` indicates a machine-precision number, which is usually (always?) an IEEE-754 double-precision number.



                You can get the result you're looking for by doing the conversion to numerical values after the squaring/cubing:



                Do[Print[StringForm["the square of `` is ``, the cube of it is ``", 
                N[i], N[i^2], N[i^3]]], {i, 1/2, 6, 1/10}]



                the square of 0.7` is 0.49`, the cube of it is 0.343`







                share|improve this answer











                $endgroup$
















                  5












                  5








                  5





                  $begingroup$

                  This is what happens when you use IEEE-754 double-precision math instead of exact math.



                  StringForm, InputForm, FullForm etc. give you all possible digits of these IEEE-754 double-precision numbers used internally. This is no different from any other programming language.



                  Other number display functions, like NumberForm, show fewer digits. The internal representation of the number doesn't change though.



                  The backtick ` indicates a machine-precision number, which is usually (always?) an IEEE-754 double-precision number.



                  You can get the result you're looking for by doing the conversion to numerical values after the squaring/cubing:



                  Do[Print[StringForm["the square of `` is ``, the cube of it is ``", 
                  N[i], N[i^2], N[i^3]]], {i, 1/2, 6, 1/10}]



                  the square of 0.7` is 0.49`, the cube of it is 0.343`







                  share|improve this answer











                  $endgroup$



                  This is what happens when you use IEEE-754 double-precision math instead of exact math.



                  StringForm, InputForm, FullForm etc. give you all possible digits of these IEEE-754 double-precision numbers used internally. This is no different from any other programming language.



                  Other number display functions, like NumberForm, show fewer digits. The internal representation of the number doesn't change though.



                  The backtick ` indicates a machine-precision number, which is usually (always?) an IEEE-754 double-precision number.



                  You can get the result you're looking for by doing the conversion to numerical values after the squaring/cubing:



                  Do[Print[StringForm["the square of `` is ``, the cube of it is ``", 
                  N[i], N[i^2], N[i^3]]], {i, 1/2, 6, 1/10}]



                  the square of 0.7` is 0.49`, the cube of it is 0.343`








                  share|improve this answer














                  share|improve this answer



                  share|improve this answer








                  edited 7 hours ago

























                  answered 7 hours ago









                  RomanRoman

                  4,91011130




                  4,91011130























                      1












                      $begingroup$

                      StringForm is very old. It goes all the back to V1.0, released in 1988. It represents an attempt by WRI to have an IO formatter that would appeal to programmers familiar with C and similar programming languages.



                      V6.0, released in 2003, added formatting tools that are not only easier to use but which are better integrated into Mathematica's way of doing things. One of the new IO formatters was Row. It does not have the problem with formatting machine numbers that you ran into by using StringForm.



                      Here is how you can get your output with Row.



                      Column[
                      Table[
                      Row[{"the square of ", i, " is ", i^2, ", the cube of it is ", i^3}],
                      {i, 0.5, 1., .1}]]


                      output



                      One of the nice features of the newer IO formatting tools is that they allow styles to be applied at almost any level. For example:



                      numStyle[num_?NumericQ] := Style[num, Red, Bold, Italic]
                      Style[
                      Column[
                      Table[
                      Row[
                      {"the square of ", numStyle[i], " is ", numStyle[i^2],
                      ", the cube of it is ", numStyle[i^3]}],
                      {i, 0.5, 1., .1}]],
                      FontFamily -> "Arial"]


                      styled



                      It isn't that you can't apply styles to StringForm output, but that it is harder to do and requires more care.






                      share|improve this answer











                      $endgroup$


















                        1












                        $begingroup$

                        StringForm is very old. It goes all the back to V1.0, released in 1988. It represents an attempt by WRI to have an IO formatter that would appeal to programmers familiar with C and similar programming languages.



                        V6.0, released in 2003, added formatting tools that are not only easier to use but which are better integrated into Mathematica's way of doing things. One of the new IO formatters was Row. It does not have the problem with formatting machine numbers that you ran into by using StringForm.



                        Here is how you can get your output with Row.



                        Column[
                        Table[
                        Row[{"the square of ", i, " is ", i^2, ", the cube of it is ", i^3}],
                        {i, 0.5, 1., .1}]]


                        output



                        One of the nice features of the newer IO formatting tools is that they allow styles to be applied at almost any level. For example:



                        numStyle[num_?NumericQ] := Style[num, Red, Bold, Italic]
                        Style[
                        Column[
                        Table[
                        Row[
                        {"the square of ", numStyle[i], " is ", numStyle[i^2],
                        ", the cube of it is ", numStyle[i^3]}],
                        {i, 0.5, 1., .1}]],
                        FontFamily -> "Arial"]


                        styled



                        It isn't that you can't apply styles to StringForm output, but that it is harder to do and requires more care.






                        share|improve this answer











                        $endgroup$
















                          1












                          1








                          1





                          $begingroup$

                          StringForm is very old. It goes all the back to V1.0, released in 1988. It represents an attempt by WRI to have an IO formatter that would appeal to programmers familiar with C and similar programming languages.



                          V6.0, released in 2003, added formatting tools that are not only easier to use but which are better integrated into Mathematica's way of doing things. One of the new IO formatters was Row. It does not have the problem with formatting machine numbers that you ran into by using StringForm.



                          Here is how you can get your output with Row.



                          Column[
                          Table[
                          Row[{"the square of ", i, " is ", i^2, ", the cube of it is ", i^3}],
                          {i, 0.5, 1., .1}]]


                          output



                          One of the nice features of the newer IO formatting tools is that they allow styles to be applied at almost any level. For example:



                          numStyle[num_?NumericQ] := Style[num, Red, Bold, Italic]
                          Style[
                          Column[
                          Table[
                          Row[
                          {"the square of ", numStyle[i], " is ", numStyle[i^2],
                          ", the cube of it is ", numStyle[i^3]}],
                          {i, 0.5, 1., .1}]],
                          FontFamily -> "Arial"]


                          styled



                          It isn't that you can't apply styles to StringForm output, but that it is harder to do and requires more care.






                          share|improve this answer











                          $endgroup$



                          StringForm is very old. It goes all the back to V1.0, released in 1988. It represents an attempt by WRI to have an IO formatter that would appeal to programmers familiar with C and similar programming languages.



                          V6.0, released in 2003, added formatting tools that are not only easier to use but which are better integrated into Mathematica's way of doing things. One of the new IO formatters was Row. It does not have the problem with formatting machine numbers that you ran into by using StringForm.



                          Here is how you can get your output with Row.



                          Column[
                          Table[
                          Row[{"the square of ", i, " is ", i^2, ", the cube of it is ", i^3}],
                          {i, 0.5, 1., .1}]]


                          output



                          One of the nice features of the newer IO formatting tools is that they allow styles to be applied at almost any level. For example:



                          numStyle[num_?NumericQ] := Style[num, Red, Bold, Italic]
                          Style[
                          Column[
                          Table[
                          Row[
                          {"the square of ", numStyle[i], " is ", numStyle[i^2],
                          ", the cube of it is ", numStyle[i^3]}],
                          {i, 0.5, 1., .1}]],
                          FontFamily -> "Arial"]


                          styled



                          It isn't that you can't apply styles to StringForm output, but that it is harder to do and requires more care.







                          share|improve this answer














                          share|improve this answer



                          share|improve this answer








                          edited 5 mins ago

























                          answered 1 hour ago









                          m_goldbergm_goldberg

                          88.4k872199




                          88.4k872199






























                              draft saved

                              draft discarded




















































                              Thanks for contributing an answer to Mathematica Stack Exchange!


                              • Please be sure to answer the question. Provide details and share your research!

                              But avoid



                              • Asking for help, clarification, or responding to other answers.

                              • Making statements based on opinion; back them up with references or personal experience.


                              Use MathJax to format equations. MathJax reference.


                              To learn more, see our tips on writing great answers.




                              draft saved


                              draft discarded














                              StackExchange.ready(
                              function () {
                              StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmathematica.stackexchange.com%2fquestions%2f194909%2fwhy-do-i-get-badly-formatted-numerical-results-when-i-use-stringform%23new-answer', 'question_page');
                              }
                              );

                              Post as a guest















                              Required, but never shown





















































                              Required, but never shown














                              Required, but never shown












                              Required, but never shown







                              Required, but never shown

































                              Required, but never shown














                              Required, but never shown












                              Required, but never shown







                              Required, but never shown







                              Popular posts from this blog

                              is 'sed' thread safeWhat should someone know about using Python scripts in the shell?Nexenta bash script uses...

                              How do i solve the “ No module named 'mlxtend' ” issue on Jupyter?

                              Pilgersdorf Inhaltsverzeichnis Geografie | Geschichte | Bevölkerungsentwicklung | Politik | Kultur...