# Writing a float to an IOStream in decimal notation

**URL:** <https://discourse.julialang.org/t/writing-a-float-to-an-iostream-in-decimal-notation/6927>\
**Category:** General Usage\
**Created:** [November 7, 2017, 6:07am UTC](https://discourse.julialang.org/t/writing-a-float-to-an-iostream-in-decimal-notation/6927 "2017-11-07T06:07:56Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![Azzaare](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/azzaare/32/21008_2.png) [@Azzaare](https://discourse.julialang.org/u/Azzaare)\
**Post date:** [November 7, 2017, 6:07am UTC](https://discourse.julialang.org/t/writing-a-float-to-an-iostream-in-decimal-notation/6927/1 "2017-11-07T06:07:56Z")

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Is there a way to force the decimal notation for floats for printing or writing in a file?

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**Author:** ![rdeits](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/rdeits/32/286_2.png) [@rdeits](https://discourse.julialang.org/u/rdeits)\
**Post date:** [November 7, 2017, 7:03am UTC](https://discourse.julialang.org/t/writing-a-float-to-an-iostream-in-decimal-notation/6927/2 "2017-11-07T07:03:46Z")

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`@sprintf` can do that:

```julia
julia> @sprintf("%.3f", Float64(π))
"3.142"

julia> @sprintf("%.8f", Float64(π))
"3.14159265"

julia> @sprintf("%.8f", 3e8)
"300000000.00000000"

```

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<div class="post-metadata">

**Author:** ![rdeits](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/rdeits/32/286_2.png) [@rdeits](https://discourse.julialang.org/u/rdeits)\
**Post date:** [November 7, 2017, 7:11am UTC](https://discourse.julialang.org/t/writing-a-float-to-an-iostream-in-decimal-notation/6927/3 "2017-11-07T07:11:27Z")

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Or, if you want to print to a stream directly, then `@printf`:

```julia
julia> @printf(STDOUT, "%f", π)
3.141593

```

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**Author:** ![sunoru](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/sunoru/32/461_2.png) [@sunoru](https://discourse.julialang.org/u/sunoru)\
**Post date:** [November 7, 2017, 7:45am UTC](https://discourse.julialang.org/t/writing-a-float-to-an-iostream-in-decimal-notation/6927/4 "2017-11-07T07:45:25Z")

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I often use `@printf` to do such printing.

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<div class="post-metadata">

**Author:** ![Azzaare](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/azzaare/32/21008_2.png) [@Azzaare](https://discourse.julialang.org/u/Azzaare)\
**Post date:** [November 7, 2017, 7:58am UTC](https://discourse.julialang.org/t/writing-a-float-to-an-iostream-in-decimal-notation/6927/5 "2017-11-07T07:58:48Z")

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Thanks @rdeits @sunoru, it did the trick.