# Replicating formatting from Fortran code output
**URL:** https://discourse.julialang.org/t/replicating-formatting-from-fortran-code-output/127036
**Category:** General Usage
**Tags:** fortran, formatting
**Created:** [March 17, 2025, 3:07am UTC](https://discourse.julialang.org/t/replicating-formatting-from-fortran-code-output/127036 "2025-03-17T03:07:07Z")
**Posts on this page:** 7
**Page:** 1
### Author:  [@trung](https://discourse.julialang.org/u/trung)
#### Post date: [March 17, 2025, 3:07am UTC](https://discourse.julialang.org/t/replicating-formatting-from-fortran-code-output/127036/1 "2025-03-17T03:07:07Z")
I am trying to replicate the formatting from a Fortran code output in Julia. Here is a MWE.
```julia
program formattest
implicit none
integer:: iyd
real(4):: d(4),t
iyd = 10000
d = 9.999e-38
t = 1.053e10
open(77,file='outputtest.txt',status='replace')
write(77,'(i7,4e13.4,f8.2)') &
iyd,d(1:4),t
close(77)
end program
```
The output that I obtain is
```julia
10000 0.9999E-37 0.9999E-37 0.9999E-37 0.9999E-37 294.10
```
Is it possible to replicate the formatting from the “0.9999E-37” in Julia?
---
### Author:  [@LaurentPlagne](https://discourse.julialang.org/u/LaurentPlagne)
#### Post date: [March 17, 2025, 5:51am UTC](https://discourse.julialang.org/t/replicating-formatting-from-fortran-code-output/127036/2 "2025-03-17T05:51:15Z")
> [@trung](#):
>
> 0.9999E-37
It looks small for `real(4)`… Did you already play with `Printf` [Printf · The Julia Language](https://docs.julialang.org/en/v1/stdlib/Printf/) ?
---
### Author:  [@trung](https://discourse.julialang.org/u/trung)
#### Post date: [March 17, 2025, 11:55am UTC](https://discourse.julialang.org/t/replicating-formatting-from-fortran-code-output/127036/3 "2025-03-17T11:55:04Z")
The 9.999E-38 is something special put in the original code so there is no way around it and I already tried to use Printf but I don’t see any way to print it as `0.9999E-37` instead of `9.999E-38`
---
### Author:  [@jmkuhn](https://discourse.julialang.org/u/jmkuhn)
#### Post date: [March 17, 2025, 1:29pm UTC](https://discourse.julialang.org/t/replicating-formatting-from-fortran-code-output/127036/4 "2025-03-17T13:29:21Z")
I don’t know of a Julia package that will do this directly. There is a Python package that you could use with PyCall
```julia
using PyCall
fortranformat = pyimport("fortranformat")
format = fortranformat.FortranRecordWriter("(i7,4e13.4,f8.2)")
iyd = 10000
d = 9.999e-38
t = 294.1
println(format.write((iyd, d, d, d, d, t)))
```
which outputs
```julia
10000 0.9999E-37 0.9999E-37 0.9999E-37 0.9999E-37 294.10
```
You would need to install PyCall with a Python environment that has the [fortranformat](https://pypi.org/project/fortranformat/) package installed. The details on how to do that depend on what OS you are using and whether you already have a Python environment installed.
---
### Author:  [@rafael.guerra](https://discourse.julialang.org/u/rafael.guerra)
#### Post date: [March 17, 2025, 3:16pm UTC](https://discourse.julialang.org/t/replicating-formatting-from-fortran-code-output/127036/5 "2025-03-17T15:16:04Z")
> [@trung](#):
>
> I don’t see any way to print it as `0.9999E-37`
Why does it matter?
---
### Author:  [@trung](https://discourse.julialang.org/u/trung)
#### Post date: [March 17, 2025, 3:24pm UTC](https://discourse.julialang.org/t/replicating-formatting-from-fortran-code-output/127036/6 "2025-03-17T15:24:01Z")
I want to be able to use `diff` in the command line for the Fortran output and the Julia output to compare them quickly instead of having to read in the Fortran output and compare both outputs in a Julia code
---
### Author:  [@PeterSimon](https://discourse.julialang.org/u/PeterSimon)
#### Post date: [March 17, 2025, 3:37pm UTC](https://discourse.julialang.org/t/replicating-formatting-from-fortran-code-output/127036/7 "2025-03-17T15:37:38Z")
> [@trung](#):
>
> I want to be able to use `diff` in the command line for the Fortran output and the Julia output to compare them quickly
Sounds like you want functionality similar to [numdiff](https://github.com/tjhei/numdiff) or [spiff](http://hpux.connect.org.uk/hppd/hpux/Text/spiff-1.0/).