--- title: "InputForm" language: "en" type: "Symbol" summary: "InputForm[expr] prints as a version of expr suitable for input to the Wolfram Language." keywords: - 1D format - ascii input syntax - linear formatting - linear input - unicode input syntax - lprint - mat2str canonical_url: "https://reference.wolfram.com/language/ref/InputForm.html" source: "Wolfram Language Documentation" related_guides: - title: "Mathematical Typesetting" link: "https://reference.wolfram.com/language/guide/MathematicalTypesetting.en.md" - title: "Display of Numbers" link: "https://reference.wolfram.com/language/guide/DisplayOfNumbers.en.md" - title: "Wolfram System Session History" link: "https://reference.wolfram.com/language/guide/WolframSystemSessionHistory.en.md" - title: "Wolfram Client Library for Python" link: "https://reference.wolfram.com/language/guide/WolframClientLibraryForPython.en.md" - title: "Converting between Expressions & Strings" link: "https://reference.wolfram.com/language/guide/ConvertingBetweenExpressionsAndStrings.en.md" - title: "Numerical Evaluation & Precision" link: "https://reference.wolfram.com/language/guide/NumericalEvaluationAndPrecision.en.md" related_functions: - title: "OutputForm" link: "https://reference.wolfram.com/language/ref/OutputForm.en.md" - title: "FullForm" link: "https://reference.wolfram.com/language/ref/FullForm.en.md" - title: "StandardForm" link: "https://reference.wolfram.com/language/ref/StandardForm.en.md" - title: "TextString" link: "https://reference.wolfram.com/language/ref/TextString.en.md" - title: "Compress" link: "https://reference.wolfram.com/language/ref/Compress.en.md" - title: "BinarySerialize" link: "https://reference.wolfram.com/language/ref/BinarySerialize.en.md" related_tutorials: - title: "Redrawing and Combining Plots" link: "https://reference.wolfram.com/language/tutorial/GraphicsAndSound.en.md#9501" - title: "Forms of Input and Output" link: "https://reference.wolfram.com/language/tutorial/TextualInputAndOutput.en.md#12368" - title: "The Interpretation of Textual Forms" link: "https://reference.wolfram.com/language/tutorial/TextualInputAndOutput.en.md#5202" - title: "The Representation of Textual Forms" link: "https://reference.wolfram.com/language/tutorial/TextualInputAndOutput.en.md#5084" --- # InputForm InputForm[expr] prints as a version of expr suitable for input to the Wolfram Language. ## Details and Options * ``InputForm`` always produces one-dimensional output, suitable to be typed as lines of Wolfram Language input. * The typeset form of ``InputForm[expr]`` is interpreted the same as ``expr`` when used in input. » * When an input evaluates to ``InputForm[expr]``, ``InputForm`` does not appear in the output. » * ``Put`` (``>>``) produces ``InputForm`` by default. * ``Short[InputForm[expr]]`` can be used, but may generate skeleton objects that cannot be given as Wolfram Language input. * The option ``NumberMarks`` can be used to specify whether ````` marks should be used to indicate type, precision, or accuracy of approximate numbers. » --- ## Examples (18) ### Basic Examples (2) ``InputForm`` of a typeset expression: ```wl In[1]:= InputForm[(x/Sqrt[5]) + y^2 + 1 / z] ``` Out[1]//InputForm= x/Sqrt[5] + y^2 + z^(-1) --- ``InputForm`` of a graphic: ```wl In[1]:= [image]//InputForm ``` Out[1]//InputForm= Graphics[{{RGBColor[1, 0, 0], Disk[{0, 0}]}, {RGBColor[0, 0, 1], Rectangle[{-1/2, -1/2}]}}] ### Scope (8) #### Basic Objects (2) ``Integer``, ``Rational``, ``Real``, and ``Complex`` numbers: ```wl In[1]:= Map[InputForm, {123, 1 / 23, 1.23, 1 + 23I}] Out[1]= {InputForm[123], InputForm[Rational[1, 23]], InputForm[1.23], InputForm[Complex[1, 23]]} ``` Arbitrary‐precision ``Real`` and ``Complex`` numbers: ```wl In[2]:= InputForm /@ N[{10 / 3, 10 / 3I}, 20] Out[2]= {InputForm[3.33333333333333333333`20.], InputForm[Complex[0, 3.33333333333333333333`20.]]} ``` Special constants: ```wl In[3]:= InputForm /@ {I, π, E} Out[3]= {InputForm[Complex[0, 1]], InputForm[Pi], InputForm[E]} ``` --- Characters and strings of characters: ```wl In[1]:= InputForm /@ {"a", "α", "⊕"} Out[1]= {InputForm["a"], InputForm["α"], InputForm["⊕"]} ``` Control characters for strings: ```wl In[2]:= InputForm["A first line A second line"] ``` Out[2]//InputForm= "A first line A second line" #### Special Input Forms (4) Different ways of representing ``Power`` expressions: ```wl In[1]:= InputForm /@ {a ^ x, a^x, a^(1/(3)), Exp[x], 1 / x, (1/x)} Out[1]= {InputForm[a^x], InputForm[a^x], InputForm[a^(Rational[1, 3])], InputForm[E^x], InputForm[x^(-1)], InputForm[x^(-1)]} ``` --- Special typeset expressions: ```wl In[1]:= InputForm /@ {y'[x], ∫y[x]\[DifferentialD]x, Subsuperscript[∑, k = 1, n]y[k], Subsuperscript[∏, k = 1, n]y[k], x∈Reals, x∧y∨z} Out[1]= {InputForm[Derivative[1][y][x]], InputForm[Integrate[y[x], x]], InputForm[Sum[y[k], {k, 1, n}]], InputForm[Product[y[k], {k, 1, n}]], InputForm[Element[x, Reals]], InputForm[(x && y) || z]} ``` --- Different list structures: ```wl In[1]:= InputForm[{1, 2, 3}] ``` Out[1]//InputForm= {1, 2, 3} ```wl In[2]:= InputForm /@ {(| | | | | - | - | - | | a | b | c | | d | e | f |), {{a, b, c}, {d, e, f}}} Out[2]= {InputForm[{{a, b, c}, {d, e, f}}], InputForm[{{a, b, c}, {d, e, f}}]} ``` --- Input without special interpretation: ```wl In[1]:= InputForm /@ {Subscript[x, a], Overscript[x, a], Underscript[x, a]} Out[1]= {InputForm[Subscript[x, a]], InputForm[Overscript[x, a]], InputForm[Underscript[x, a]]} ``` With special characters in the same positions, there may be special interpretations: ```wl In[2]:= InputForm /@ {Subscript[x, - ], Overscript[x, _], Underscript[x, _]} Out[2]= {InputForm[SubMinus[x]], InputForm[OverBar[x]], InputForm[UnderBar[x]]} ``` In the case of superscripts, most things get interpreted as ``Power``: ```wl In[3]:= InputForm /@ {x^a, Subsuperscript[x, b, a], x^†} Out[3]= {InputForm[x^a], InputForm[Subscript[x, b]^a], InputForm[SuperDagger[x]]} ``` #### Special Output Forms (2) Some objects use a special output representation: ```wl In[1]:= Series[Sin[x], {x, 0, 3}] Out[1]= SeriesData[x, 0, {1, 0, Rational[-1, 6]}, 1, 4, 1] In[2]:= InputForm[%] ``` Out[2]//InputForm= SeriesData[x, 0, {1, 0, -1/6}, 1, 4, 1] --- Some objects use an elided output representation: ```wl In[1]:= i = Interpolation[{1, 2, 3, 1}] Out[1]= InterpolatingFunction[{{1, 4}}, {5, 3, 0, {4}, {4}, 0, 0, 0, 0, Automatic, {}, {}, False}, {{1, 2, 3, 4}}, {{1}, {2}, {3}, {1}}, {Automatic}] In[2]:= s = SparseArray[{{1, 2} -> 1}, {5, 5}] Out[2]= SparseArray[Automatic, {5, 5}, 0, {1, {{0, 1, 1, 1, 1, 1}, {{2}}}, {1}}] ``` The elided parts are visible using ``InputForm``: ```wl In[3]:= InputForm[i] ``` Out[3]//InputForm= InterpolatingFunction[{{1, 4}}, {5, 3, 0, {4}, {4}, 0, 0, 0, 0, Automatic, {}, {}, False}, {{1, 2, 3, 4}}, {{1}, {2}, {3}, {1}}, {Automatic}] ```wl In[4]:= InputForm[s] ``` Out[4]//InputForm= SparseArray[Automatic, {5, 5}, 0, {1, {{0, 1, 1, 1, 1, 1}, {{2}}}, {1}}] ### Options (3) #### NumberMarks (3) Machine numbers format without number marks by default: ```wl In[1]:= InputForm[N[1 / 3]] ``` Out[1]//InputForm= 0.3333333333333333 The same number with number marks: ```wl In[2]:= InputForm[N[1 / 3], NumberMarks -> True] ``` Out[2]//InputForm= 0.333333 --- Extended-precision numbers include number marks by default: ```wl In[1]:= InputForm[N[10 / 3, 20]] ``` Out[1]//InputForm= 3.3333333333333333333 Without number marks: ```wl In[2]:= InputForm[N[10 / 3, 20], NumberMarks -> False] ``` Out[2]//InputForm= 3.33333333333333333333 --- A mixed symbolic and numeric expression: ```wl In[1]:= expr = N[10, 4]Sin[.25x] Out[1]= 10.00 Sin[0.25 x] In[2]:= InputForm[expr] ``` Out[2]//InputForm= 10.\`4.\*Sin[0.25\*x] Include number marks for all numbers: ```wl In[3]:= InputForm[expr, NumberMarks -> True] ``` Out[3]//InputForm= 10.\`4.\*Sin[0.25\`\*x] Omit all number marks: ```wl In[4]:= InputForm[expr, NumberMarks -> False] ``` Out[4]//InputForm= 10.\*Sin[0.25\*x] ### Properties & Relations (4) The typeset form of ``InputForm[expr]`` is interpreted the same as ``expr`` when used in input: ```wl In[1]:= {InputForm[x ^ 2]} Out[1]= {InputForm[x^2]} ``` Copy the output and paste it into an input cell. The ``InputForm[x^2]`` is interpreted as ``x^2`` : ```wl In[2]:= {InputForm[x^2]} Out[2]= {x^2} ``` --- When an input evaluates to ``InputForm[expr]``, ``InputForm`` does not appear in the output: ```wl In[1]:= InputForm[x ^ 2] ``` Out[1]//InputForm= x^2 ``Out`` is assigned the value ``x^2``, not ``InputForm[x ^ 2]`` : ```wl In[2]:= % Out[2]= x^2 ``` --- ``InputForm`` has a linear formatting: ```wl In[1]:= InputForm[Exp[I x / n]] ``` Out[1]//InputForm= E^((I\*x)/n) ``FullForm`` has linear formatting without special syntax: ```wl In[2]:= FullForm[Exp[I x / n]] Out[2]//FullForm= Power[E, Times[Complex[0, 1], Power[n, -1], x]] ``` ``OutputForm``, ``StandardForm``, and ``TraditionalForm`` all provide two-dimensional formatting: ```wl In[3]:= OutputForm[Exp[I x / n]] ``` Out[3]//OutputForm= E^((I*x)/n) ```wl In[4]:= StandardForm[Exp[I x / n]] Out[4]//StandardForm= E^(I x/n) In[5]:= TraditionalForm[Exp[I x / n]] Out[5]//TraditionalForm= $$e^{\frac{i x}{n}}$$ ``` --- Use ``ToString`` to generate a string in input form: ```wl In[1]:= ToString[(1/a) + x^2, InputForm] Out[1]= "a^(-1) + x^2" In[2]:= Head[%] Out[2]= String ``` ### Possible Issues (1) Even when an output omits ``InputForm`` from the top level, it is not stripped from subexpressions: ```wl In[1]:= e = InputForm[x ^ 2] ``` Out[1]//InputForm= x^2 The output does not have ``InputForm`` in it: ```wl In[2]:= % Out[2]= x^2 ``` However, the variable ``e`` does have ``InputForm`` in it, which may affect subsequent evaluations: ```wl In[3]:= FullForm[e] Out[3]//FullForm= InputForm[Power[x, 2]] ``` The product is not evaluated due to the intervening ``InputForm`` : ```wl In[4]:= x * e Out[4]= x InputForm[x^2] ``` Assign variables first and then apply ``InputForm`` to the result to maintain computability: ```wl In[5]:= (f = x ^ 2)//InputForm ``` Out[5]//InputForm= x^2 ```wl In[6]:= x * f Out[6]= x^3 ``` ## See Also * [`OutputForm`](https://reference.wolfram.com/language/ref/OutputForm.en.md) * [`FullForm`](https://reference.wolfram.com/language/ref/FullForm.en.md) * [`StandardForm`](https://reference.wolfram.com/language/ref/StandardForm.en.md) * [`TextString`](https://reference.wolfram.com/language/ref/TextString.en.md) * [`Compress`](https://reference.wolfram.com/language/ref/Compress.en.md) * [`BinarySerialize`](https://reference.wolfram.com/language/ref/BinarySerialize.en.md) ## Tech Notes * [Redrawing and Combining Plots](https://reference.wolfram.com/language/tutorial/GraphicsAndSound.en.md#9501) * [Forms of Input and Output](https://reference.wolfram.com/language/tutorial/TextualInputAndOutput.en.md#12368) * [The Interpretation of Textual Forms](https://reference.wolfram.com/language/tutorial/TextualInputAndOutput.en.md#5202) * [The Representation of Textual Forms](https://reference.wolfram.com/language/tutorial/TextualInputAndOutput.en.md#5084) ## Related Guides * [Mathematical Typesetting](https://reference.wolfram.com/language/guide/MathematicalTypesetting.en.md) * [Display of Numbers](https://reference.wolfram.com/language/guide/DisplayOfNumbers.en.md) * [Wolfram System Session History](https://reference.wolfram.com/language/guide/WolframSystemSessionHistory.en.md) * [Wolfram Client Library for Python](https://reference.wolfram.com/language/guide/WolframClientLibraryForPython.en.md) * [Converting between Expressions & Strings](https://reference.wolfram.com/language/guide/ConvertingBetweenExpressionsAndStrings.en.md) * [Numerical Evaluation & Precision](https://reference.wolfram.com/language/guide/NumericalEvaluationAndPrecision.en.md) ## Related Links * [An Elementary Introduction to the Wolfram Language: Strings and Text](https://www.wolfram.com/language/elementary-introduction/11-strings-and-text.html) * [An Elementary Introduction to the Wolfram Language: Real-World Data](https://www.wolfram.com/language/elementary-introduction/16-real-world-data.html) * [An Elementary Introduction to the Wolfram Language: Units](https://www.wolfram.com/language/elementary-introduction/17-units.html) * [An Elementary Introduction to the Wolfram Language: Dates and Times](https://www.wolfram.com/language/elementary-introduction/19-dates-and-times.html) * [NKS\|Online](http://www.wolframscience.com/nks/search/?q=InputForm) * [A New Kind of Science](http://www.wolframscience.com/nks/) ## History * Introduced in 1988 (1.0) \| Updated in 1996 (3.0)