nushell/docs/commands/math-eval.md

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# math eval
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math eval is a command that takes a math expression from the pipeline and evaluates that into a number. It also optionally takes the math expression as an argument.
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This command supports the following operations -
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operations:
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* binary operators: +, -, *, /, % (remainder), ^ (power)
* unary operators: +, -, ! (factorial)
functions:
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* sqrt, abs
* exp, ln, log10
* sin, cos, tan, asin, acos, atan, atan2
* sinh, cosh, tanh, asinh, acosh, atanh
* floor, ceil, round
* signum
* max(x, ...), min(x, ...): maximum and minimum of 1 or more numbers
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constants:
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* pi
* e
## Examples
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```shell
> echo "1+2+3" | math eval
6.0u
```
```shell
> echo "1-2+3" | math eval
2.0
```
```shell
> echo "-(-23)" | math eval
23.0
```
```shell
> echo "5^2" | math eval
25.0
```
```shell
> echo "5^3" | math eval
125.0
```
```shell
> echo "min(5,4,3,2,1,0,-100,45)" | math eval
-100.0
```
```shell
> echo "max(5,4,3,2,1,0,-100,45)" | math eval
45.0
```
```shell
> echo sqrt(2) | math eval
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1.414213562373095
```
```shell
> echo pi | math eval
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3.141592653589793
```
```shell
> echo e | math eval
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2.718281828459045
```
```shell
> echo "sin(pi / 2)" | math eval
1.0
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```
```shell
> echo "floor(5999/1000)" | math eval
5.0
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```
```shell
> open abc.json
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───┬──────
# │ size
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───┼──────
0 │ 816
1 │ 1627
2 │ 1436
3 │ 1573
4 │ 935
5 │ 52
6 │ 999
7 │ 1639
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───┴──────
```
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```shell
> open abc.json | format "({size} + 500) * 4"
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───┬──────────────────
# │
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───┼──────────────────
0 │ (816 + 500) * 4
1 │ (1627 + 500) * 4
2 │ (1436 + 500) * 4
3 │ (1573 + 500) * 4
4 │ (935 + 500) * 4
5 │ (52 + 500) * 4
6 │ (999 + 500) * 4
7 │ (1639 + 500) * 4
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───┴──────────────────
```
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```shell
> open abc.json | format "({size} + 500) * 4" | math eval
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───┬───────────
# │
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───┼───────────
0 │ 5264.0000
1 │ 8508.0000
2 │ 7744.0000
3 │ 8292.0000
4 │ 5740.0000
5 │ 2208.0000
6 │ 5996.0000
7 │ 8556.0000
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───┴───────────
```
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```shell
> open abc.json | format "({size} - 1000) * 4" | math eval
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───┬────────────
# │
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───┼────────────
0 │ -736.0000
1 │ 2508.0000
2 │ 1744.0000
3 │ 2292.0000
4 │ -260.0000
5 │ -3792.0000
6 │ -4.0000
7 │ 2556.0000
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───┴────────────
```
Note that since `math eval` uses floating-point numbers, the result may not always be precise.
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```shell
> echo "floor(5999999999999999999/1000000000000000000)" | math eval
6.0
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```