Can't install gmpy on Windows

Question

I tried to pip install gmpy but it didn't work.

Here's the error:

PS C:\Users\ADMIN\Downloads> pip install gmpy
Collecting gmpy
  Using cached gmpy-1.17.zip (147 kB)
  Installing build dependencies ... done
  Getting requirements to build wheel ... done
  Preparing metadata (pyproject.toml) ... done
Building wheels for collected packages: gmpy
  Building wheel for gmpy (pyproject.toml) ... error 
  error: subprocess-exited-with-error

  × Building wheel for gmpy (pyproject.toml) did not run successfully.
  │ exit code: 1
  ╰─> [3 lines of output]
      gmpy.c
      src/gmpy.c(243): fatal error C1083: Cannot open include file: 'longintrepr.h': No such file or directory
      error: command 'C:\\Program Files (x86)\\Microsoft Visual Studio\\2022\\BuildTools\\VC\\Tools\\MSVC\\14.37.32822\\bin\\HostX86\\x64\\cl.exe' failed with exit code 2
      [end of output]

  note: This error originates from a subprocess, and is likely not a problem with pip.
  ERROR: Failed building wheel for gmpy
Failed to build gmpy
ERROR: Could not build wheels for gmpy, which is required to install pyproject.toml-based projects

However, pip install gmpy2 and others worked.

I tried to import both of them:

Here's the part I need to calculate:

N = 17740803753336460891508014077951088945415214329359164945595622460861617151883658129377771074141448545977293824812472806768754107334272113784618671425945265453677763300584120796664192793654787317526905676618168560287204392207536711238413377822113265783504873957094131330620182217422910507867161033695120195691266283498385072573721376398480018719760538723050237163598524153522595496137288270407836138586188296538117138982579560625325815068701431157466298638302885600982291990551448117534677697122276691651611734934147801954625280213769902451417946572231015611006746186167211313556716518863585799128114202130873384852581
e = 65537
ct = 7617664236008252568996899627946125782926068188323112773389474654757630578865481085502759186904920518615173703165984894164411436709177950136929724052191922739861682189280802963747906815275683543148623167088950096943169566195634558711652670745197446307315888349532981492405588457559228674864147994684328968321710022127803384848143475788457274558988285904875669797926919759123645348144531804252200718312650929926931919262408975771593313266992606751663814830129337536342634243623652919127335934704778878412649409415730419077839365246227059700689395639431013008985996793686430486195007712091309878718060405038405039494286
a = sqrt(N) +1 
b = (a*a) - N # if I use gmpy2 instead of gmpy, the result will be wrong
#p = a - sqrt((b)) gmpy2 return b as a negative number, so I can't calculate p
p = 133194608574583306560585537741344865434566457335756913474195376386565743253745136529892878182973405477415063521701522490974580141634005077732157132519942995782242635825758964371685299620951981666567270659322471350406909271667819474931143113141023059424058315681431599980321513448212682539665160717948701866681 
# for this result, I used gmpy in sagemath in Ubuntu.

Answer 1

gmpy is no longer maintained, you should use gmpy2. In this case what you need is gmpy2.isqrt(n) which return the integer part of the square root of n.

The difference between isqrt and sqrt in gmpy2 is that sqrt support floating numbers but it can't be used for big numbers in cryptography.

source:

• isqrt
• sqrt