---
title: "ClikaRT::dtype::float8_e4m3fn_t"
sidebar_label: "float8_e4m3fn_t"
description: "FP8 E4M3 (FN: finite, NaN-only): 1 sign + 4 exponent + 3 mantissa, bias 7. Range ±448, smallest normal 2^-6, eps 2^-3. NaN at exp+mantissa all-ones; no infinity."
---

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<span class="api-kind api-kind--struct">struct</span>

**Header:** `ClikaRT/compute/scalar_types.h`

FP8 E4M3 (FN: finite, NaN-only): 1 sign + 4 exponent + 3 mantissa, bias 7. Range ±448, smallest normal 2^-6, eps 2^-3. NaN at exp+mantissa all-ones; no infinity. Conversion from fp32 saturates on overflow. 8-bit storage.

## Static member functions

### from\_bits() {#from_bits}

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`static` `constexpr` [`float8_e4m3fn_t`](./float8_e4m3fn_t.md) **`from_bits`**(`std::uint8_t` `b`) `noexcept`

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Reinterpret a raw 8-bit encoding without converting.

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Declared in `ClikaRT/compute/scalar_types.h`, line 140

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## Member functions

### float8\_e4m3fn\_t() {#float8_e4m3fn_t}

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`constexpr` `constexpr` **`float8_e4m3fn_t`**() `noexcept=default`

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Declared in `ClikaRT/compute/scalar_types.h`, line 131

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### float8\_e4m3fn\_t(float) {#float8_e4m3fn_t-2}

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`explicit` **`float8_e4m3fn_t`**(`float` `f`) `noexcept`

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Convert from fp32 (round-to-nearest-even; saturates on overflow).

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Declared in `ClikaRT/compute/scalar_types.h`, line 134

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### operator float() {#operator-float}

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**`operator float`**() `const noexcept`

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Convert to fp32 (lossless).

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Declared in `ClikaRT/compute/scalar_types.h`, line 137

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### is\_nan() {#is_nan}

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`constexpr` `bool` **`is_nan`**() `const noexcept`

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True at the format's NaN (exponent+mantissa all-ones; either sign).

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Declared in `ClikaRT/compute/scalar_types.h`, line 142

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## Data members

### bits {#bits}

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`std::uint8_t` **`bits`** `= 0`

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Raw 8-bit encoding (the storage/ABI form).

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Declared in `ClikaRT/compute/scalar_types.h`, line 129

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## Friends

### operator== {#operator-eq}

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`friend` `bool` **`operator==`**([`float8_e4m3fn_t`](./float8_e4m3fn_t.md) `a`, [`float8_e4m3fn_t`](./float8_e4m3fn_t.md) `b`) `noexcept`

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Compares `a` and `b` by dequantized value (IEEE rules; a NaN operand compares false).

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Declared in `ClikaRT/compute/scalar_types.h`, line 144

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### operator\!= {#operator-ne}

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`friend` `bool` **`operator!=`**([`float8_e4m3fn_t`](./float8_e4m3fn_t.md) `a`, [`float8_e4m3fn_t`](./float8_e4m3fn_t.md) `b`) `noexcept`

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Compares `a` and `b` by dequantized value (IEEE rules; a NaN operand compares false).

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Declared in `ClikaRT/compute/scalar_types.h`, line 145

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### operator\< {#operator-lt}

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`friend` `bool` **`operator<`**([`float8_e4m3fn_t`](./float8_e4m3fn_t.md) `a`, [`float8_e4m3fn_t`](./float8_e4m3fn_t.md) `b`) `noexcept`

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Compares `a` and `b` by dequantized value (IEEE rules; a NaN operand compares false).

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Declared in `ClikaRT/compute/scalar_types.h`, line 146

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### operator\<= {#operator-le}

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`friend` `bool` **`operator<=`**([`float8_e4m3fn_t`](./float8_e4m3fn_t.md) `a`, [`float8_e4m3fn_t`](./float8_e4m3fn_t.md) `b`) `noexcept`

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Compares `a` and `b` by dequantized value (IEEE rules; a NaN operand compares false).

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Declared in `ClikaRT/compute/scalar_types.h`, line 147

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### operator\> {#operator-gt}

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`friend` `bool` **`operator>`**([`float8_e4m3fn_t`](./float8_e4m3fn_t.md) `a`, [`float8_e4m3fn_t`](./float8_e4m3fn_t.md) `b`) `noexcept`

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Compares `a` and `b` by dequantized value (IEEE rules; a NaN operand compares false).

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Declared in `ClikaRT/compute/scalar_types.h`, line 148

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### operator\>= {#operator-ge}

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`friend` `bool` **`operator>=`**([`float8_e4m3fn_t`](./float8_e4m3fn_t.md) `a`, [`float8_e4m3fn_t`](./float8_e4m3fn_t.md) `b`) `noexcept`

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Compares `a` and `b` by dequantized value (IEEE rules; a NaN operand compares false).

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Declared in `ClikaRT/compute/scalar_types.h`, line 149

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