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3 | # Function log
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4 |
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5 | Calculate the logarithm of a value.
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6 |
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7 | For matrices, the function is evaluated element wise.
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8 |
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9 |
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10 | ## Syntax
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11 |
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12 | ```js
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13 | math.log(x)
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14 | math.log(x, base)
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15 | ```
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16 |
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17 | ### Parameters
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18 |
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19 | Parameter | Type | Description
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20 | --------- | ---- | -----------
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21 | `x` | number | BigNumber | Complex | Array | Matrix | Value for which to calculate the logarithm.
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22 | `base` | number | BigNumber | Complex | Optional base for the logarithm. If not provided, the natural logarithm of `x` is calculated. Default value: e.
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23 |
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24 | ### Returns
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25 |
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26 | Type | Description
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27 | ---- | -----------
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28 | number | BigNumber | Complex | Array | Matrix | Returns the logarithm of `x`
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29 |
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30 |
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31 | ## Examples
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32 |
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33 | ```js
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34 | math.log(3.5) // returns 1.252762968495368
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35 | math.exp(math.log(2.4)) // returns 2.4
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36 |
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37 | math.pow(10, 4) // returns 10000
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38 | math.log(10000, 10) // returns 4
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39 | math.log(10000) / math.log(10) // returns 4
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40 |
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41 | math.log(1024, 2) // returns 10
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42 | math.pow(2, 10) // returns 1024
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43 | ```
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44 |
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45 |
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46 | ## See also
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47 |
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48 | [exp](exp.md),
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49 | [log2](log2.md),
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50 | [log10](log10.md),
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51 | [log1p](log1p.md)
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