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Module `deepbook::math`

crates/sui-framework/docs/deepbook/math.md

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<pre><code></code></pre>

<a name="@Constants_0"></a>

Constants

<a name="deepbook_math_FLOAT_SCALING"></a>

scaling setting for float

<pre><code><b>const</b> <a href="../deepbook/math.md#deepbook_math_FLOAT_SCALING">FLOAT_SCALING</a>: u64 = 1000000000; </code></pre>

<a name="deepbook_math_FLOAT_SCALING_U128"></a>

<pre><code><b>const</b> <a href="../deepbook/math.md#deepbook_math_FLOAT_SCALING_U128">FLOAT_SCALING_U128</a>: u128 = 1000000000; </code></pre>

<a name="deepbook_math_EUnderflow"></a>

<pre><code><b>const</b> <a href="../deepbook/math.md#deepbook_math_EUnderflow">EUnderflow</a>: u64 = 1; </code></pre>

<a name="deepbook_math_unsafe_mul"></a>

Function unsafe_mul

<pre><code><b>public</b>(package) <b>fun</b> <a href="../deepbook/math.md#deepbook_math_unsafe_mul">unsafe_mul</a>(x: u64, y: u64): u64 </code></pre> <details> <summary>Implementation</summary> <pre><code><b>public</b>(package) <b>fun</b> <a href="../deepbook/math.md#deepbook_math_unsafe_mul">unsafe_mul</a>(x: u64, y: u64): u64 { <b>let</b> (_, result) = <a href="../deepbook/math.md#deepbook_math_unsafe_mul_round">unsafe_mul_round</a>(x, y); result } </code></pre> </details>

<a name="deepbook_math_unsafe_mul_round"></a>

Function unsafe_mul_round

<pre><code><b>public</b>(package) <b>fun</b> <a href="../deepbook/math.md#deepbook_math_unsafe_mul_round">unsafe_mul_round</a>(x: u64, y: u64): (bool, u64) </code></pre> <details> <summary>Implementation</summary> <pre><code><b>public</b>(package) <b>fun</b> <a href="../deepbook/math.md#deepbook_math_unsafe_mul_round">unsafe_mul_round</a>(x: u64, y: u64): (bool, u64) { <b>let</b> x = x <b>as</b> u128; <b>let</b> y = y <b>as</b> u128; <b>let</b> <b>mut</b> is_round_down = <b>true</b>; <b>if</b> ((x * y) % <a href="../deepbook/math.md#deepbook_math_FLOAT_SCALING_U128">FLOAT_SCALING_U128</a> == 0) is_round_down = <b>false</b>; (is_round_down, (x * y / <a href="../deepbook/math.md#deepbook_math_FLOAT_SCALING_U128">FLOAT_SCALING_U128</a>) <b>as</b> u64) } </code></pre> </details>

<a name="deepbook_math_mul"></a>

Function mul

<pre><code><b>public</b> <b>fun</b> <a href="../deepbook/math.md#deepbook_math_mul">mul</a>(x: u64, y: u64): u64 </code></pre> <details> <summary>Implementation</summary> <pre><code><b>public</b> <b>fun</b> <a href="../deepbook/math.md#deepbook_math_mul">mul</a>(x: u64, y: u64): u64 { <b>let</b> (_, result) = <a href="../deepbook/math.md#deepbook_math_unsafe_mul_round">unsafe_mul_round</a>(x, y); <b>assert</b>!(result &gt; 0, <a href="../deepbook/math.md#deepbook_math_EUnderflow">EUnderflow</a>); result } </code></pre> </details>

<a name="deepbook_math_mul_round"></a>

Function mul_round

<pre><code><b>public</b> <b>fun</b> <a href="../deepbook/math.md#deepbook_math_mul_round">mul_round</a>(x: u64, y: u64): (bool, u64) </code></pre> <details> <summary>Implementation</summary> <pre><code><b>public</b> <b>fun</b> <a href="../deepbook/math.md#deepbook_math_mul_round">mul_round</a>(x: u64, y: u64): (bool, u64) { <b>let</b> (is_round_down, result) = <a href="../deepbook/math.md#deepbook_math_unsafe_mul_round">unsafe_mul_round</a>(x, y); <b>assert</b>!(result &gt; 0, <a href="../deepbook/math.md#deepbook_math_EUnderflow">EUnderflow</a>); (is_round_down, result) } </code></pre> </details>

<a name="deepbook_math_unsafe_div"></a>

Function unsafe_div

<pre><code><b>public</b>(package) <b>fun</b> <a href="../deepbook/math.md#deepbook_math_unsafe_div">unsafe_div</a>(x: u64, y: u64): u64 </code></pre> <details> <summary>Implementation</summary> <pre><code><b>public</b>(package) <b>fun</b> <a href="../deepbook/math.md#deepbook_math_unsafe_div">unsafe_div</a>(x: u64, y: u64): u64 { <b>let</b> (_, result) = <a href="../deepbook/math.md#deepbook_math_unsafe_div_round">unsafe_div_round</a>(x, y); result } </code></pre> </details>

<a name="deepbook_math_unsafe_div_round"></a>

Function unsafe_div_round

<pre><code><b>public</b>(package) <b>fun</b> <a href="../deepbook/math.md#deepbook_math_unsafe_div_round">unsafe_div_round</a>(x: u64, y: u64): (bool, u64) </code></pre> <details> <summary>Implementation</summary> <pre><code><b>public</b>(package) <b>fun</b> <a href="../deepbook/math.md#deepbook_math_unsafe_div_round">unsafe_div_round</a>(x: u64, y: u64): (bool, u64) { <b>let</b> x = x <b>as</b> u128; <b>let</b> y = y <b>as</b> u128; <b>let</b> <b>mut</b> is_round_down = <b>true</b>; <b>if</b> ((x * (<a href="../deepbook/math.md#deepbook_math_FLOAT_SCALING">FLOAT_SCALING</a> <b>as</b> u128) % y) == 0) is_round_down = <b>false</b>; (is_round_down, (x * (<a href="../deepbook/math.md#deepbook_math_FLOAT_SCALING">FLOAT_SCALING</a> <b>as</b> u128) / y) <b>as</b> u64) } </code></pre> </details>

<a name="deepbook_math_div_round"></a>

Function div_round

<pre><code><b>public</b> <b>fun</b> <a href="../deepbook/math.md#deepbook_math_div_round">div_round</a>(x: u64, y: u64): (bool, u64) </code></pre> <details> <summary>Implementation</summary> <pre><code><b>public</b> <b>fun</b> <a href="../deepbook/math.md#deepbook_math_div_round">div_round</a>(x: u64, y: u64): (bool, u64) { <b>let</b> (is_round_down, result) = <a href="../deepbook/math.md#deepbook_math_unsafe_div_round">unsafe_div_round</a>(x, y); <b>assert</b>!(result &gt; 0, <a href="../deepbook/math.md#deepbook_math_EUnderflow">EUnderflow</a>); (is_round_down, result) } </code></pre> </details>

<a name="deepbook_math_count_leading_zeros"></a>

Function count_leading_zeros

<pre><code><b>public</b>(package) <b>fun</b> <a href="../deepbook/math.md#deepbook_math_count_leading_zeros">count_leading_zeros</a>(x: u128): u8 </code></pre> <details> <summary>Implementation</summary> <pre><code><b>public</b>(package) <b>fun</b> <a href="../deepbook/math.md#deepbook_math_count_leading_zeros">count_leading_zeros</a>(<b>mut</b> x: u128): u8 { <b>if</b> (x == 0) { 128 } <b>else</b> { <b>let</b> <b>mut</b> n: u8 = 0; <b>if</b> (x & 0xFFFFFFFFFFFFFFFF0000000000000000 == 0) { // x's higher 64 is all zero, shift the lower part over x = x &lt;&lt; 64; n = n + 64; }; <b>if</b> (x & 0xFFFFFFFF000000000000000000000000 == 0) { // x's higher 32 is all zero, shift the lower part over x = x &lt;&lt; 32; n = n + 32; }; <b>if</b> (x & 0xFFFF0000000000000000000000000000 == 0) { // x's higher 16 is all zero, shift the lower part over x = x &lt;&lt; 16; n = n + 16; }; <b>if</b> (x & 0xFF000000000000000000000000000000 == 0) { // x's higher 8 is all zero, shift the lower part over x = x &lt;&lt; 8; n = n + 8; }; <b>if</b> (x & 0xF0000000000000000000000000000000 == 0) { // x's higher 4 is all zero, shift the lower part over x = x &lt;&lt; 4; n = n + 4; }; <b>if</b> (x & 0xC0000000000000000000000000000000 == 0) { // x's higher 2 is all zero, shift the lower part over x = x &lt;&lt; 2; n = n + 2; }; <b>if</b> (x & 0x80000000000000000000000000000000 == 0) { n = n + 1; }; n } } </code></pre> </details>