# OpenFHE CKKS drop in accuracy after upgrading to 1.2

**URL:** <https://openfhe.discourse.group/t/openfhe-ckks-drop-in-accuracy-after-upgrading-to-1-2/1432>\
**Category:** Library Questions\
**Tags:** openfhe-help\
**Created:** [July 15, 2024, 3:50pm UTC](https://openfhe.discourse.group/t/openfhe-ckks-drop-in-accuracy-after-upgrading-to-1-2/1432 "2024-07-15T15:50:32Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![lema](https://yyz1.discourse-cdn.com/flex031/user_avatar/openfhe.discourse.group/lema/32/255_2.png) [@lema](https://openfhe.discourse.group/u/lema)\
**Post date:** [July 15, 2024, 3:50pm UTC](https://openfhe.discourse.group/t/openfhe-ckks-drop-in-accuracy-after-upgrading-to-1-2/1432/1 "2024-07-15T15:50:32Z")

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Hi,

I’m testing matrix multiplication in OpenFHE+CKKS, implemented using the usual diagonal method. The matmul consists of EvalMult/EvalAdd/EvalRotation operations.  
When evaluating using OpenFHE version 1.1.4 I can get to within 1e-7 accuracy when comparing the decrypted result to a clear matrix multiplied result.  
After upgrading to 1.2, without changing anything else, this drops to 1e-6 (and 1e-5 for higher dimensions) accuracy. Is this expected? ie. Is there any change in this version that you would expect makes the accuracy drop?

These are the parameters I’m using:

```auto
  CCParams<CryptoContextCKKSRNS> parameters;
  parameters.SetSecurityLevel(HEStd_128_classic);
  parameters.SetMultiplicativeDepth(multiplicativeDepth);
  parameters.SetScalingTechnique(FIXEDAUTO);
  auto cc = GenCryptoContext(parameters);
  cc->Enable(PKE);
  cc->Enable(KEYSWITCH);
  cc->Enable(LEVELEDSHE);
  cc->Enable(ADVANCEDSHE);

```

Thanks!

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<div class="post-metadata">

**Author:** ![ypolyakov](https://yyz1.discourse-cdn.com/flex031/user_avatar/openfhe.discourse.group/ypolyakov/32/47_2.png) [@ypolyakov](https://openfhe.discourse.group/u/ypolyakov)\
**Post date:** [July 15, 2024, 10:34pm UTC](https://openfhe.discourse.group/t/openfhe-ckks-drop-in-accuracy-after-upgrading-to-1-2/1432/2 "2024-07-15T22:34:19Z")

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Could you provide all parameters for crypto context generation, e.g., the multiplicative depth? Was the default scaling factor (of 50 bits) used? What CMAKE flags were used (if any custom ones were provided)?