Why do I get badly formatted numerical results when I use StringForm? The 2019 Stack Overflow...
Should I use my personal or workplace e-mail when registering to external websites for work purpose?
Is domain driven design an anti-SQL pattern?
Why is the maximum length of OpenWrt’s root password 8 characters?
It's possible to achieve negative score?
Why do UK politicians seemingly ignore opinion polls on Brexit?
How do you say "canon" as in "official for a story universe"?
What is the motivation for a law requiring 2 parties to consent for recording a conversation
What are the motivations for publishing new editions of an existing textbook, beyond new discoveries in a field?
Why is my p-value correlated to difference between means in two sample tests?
I see my dog run
Pristine Bit Checking
How to deal with fear of taking dependencies
Springs with some finite mass
A poker game description that does not feel gimmicky
How come people say “Would of”?
How to answer pointed "are you quitting" questioning when I don't want them to suspect
Falsification in Math vs Science
Lethal sonic weapons
Where does the "burst of radiance" from Holy Weapon originate?
Are USB sockets on wall outlets live all the time, even when the switch is off?
How can I fix this gap between bookcases I made?
Is this food a bread or a loaf?
How was Skylab's orbit inclination chosen?
How to change the limits of integration
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
$begingroup$
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?
output-formatting number-form
$endgroup$
add a comment |
$begingroup$
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?
output-formatting number-form
$endgroup$
add a comment |
$begingroup$
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?
output-formatting number-form
$endgroup$
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
output-formatting number-form
edited 3 mins ago
m_goldberg
88.4k872199
88.4k872199
asked 7 hours ago
zyyzyy
1236
1236
add a comment |
add a comment |
2 Answers
2
active
oldest
votes
$begingroup$
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`
$endgroup$
add a comment |
$begingroup$
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}]]
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"]
It isn't that you can't apply styles to StringForm
output, but that it harder to do and requires more care.
$endgroup$
add a comment |
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
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
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
$begingroup$
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`
$endgroup$
add a comment |
$begingroup$
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`
$endgroup$
add a comment |
$begingroup$
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`
$endgroup$
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`
edited 7 hours ago
answered 7 hours ago
RomanRoman
4,91011130
4,91011130
add a comment |
add a comment |
$begingroup$
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}]]
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"]
It isn't that you can't apply styles to StringForm
output, but that it harder to do and requires more care.
$endgroup$
add a comment |
$begingroup$
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}]]
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"]
It isn't that you can't apply styles to StringForm
output, but that it harder to do and requires more care.
$endgroup$
add a comment |
$begingroup$
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}]]
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"]
It isn't that you can't apply styles to StringForm
output, but that it harder to do and requires more care.
$endgroup$
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}]]
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"]
It isn't that you can't apply styles to StringForm
output, but that it harder to do and requires more care.
edited 2 mins ago
answered 1 hour ago
m_goldbergm_goldberg
88.4k872199
88.4k872199
add a comment |
add a comment |
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.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
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
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
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