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@wassname
wassname / jaccard_coef_loss.py
Last active January 30, 2024 15:45
jaccard_coef_loss for keras. This loss is usefull when you have unbalanced classes within a sample such as segmenting each pixel of an image. For example you are trying to predict if each pixel is cat, dog, or background. You may have 80% background, 10% dog, and 10% cat. Should a model that predicts 100% background be 80% right, or 30%? Categor…
from keras import backend as K
def jaccard_distance_loss(y_true, y_pred, smooth=100):
"""
Jaccard = (|X & Y|)/ (|X|+ |Y| - |X & Y|)
= sum(|A*B|)/(sum(|A|)+sum(|B|)-sum(|A*B|))
The jaccard distance loss is usefull for unbalanced datasets. This has been
shifted so it converges on 0 and is smoothed to avoid exploding or disapearing
gradient.
@sonots
sonots / preprocessor.pyx
Created October 13, 2017 15:54
preprocessor in cython
# A trick to embed preprocessors in cython
cdef extern from *:
cdef void EMIT_IF_PYTHON_VERSION_HEX_LT_37 "#if PY_VERSION_HEX < 0x03070000 //" ()
cdef void EMIT_ELSE "#else //" ()
cdef void EMIT_ENDIF "#endif //" ()
EMIT_IF_PYTHON_VERSION_HEX_LT_37()
EMIT_ELSE()
@JohanAR
JohanAR / PolynomialRegression.h
Last active January 20, 2020 14:46 — forked from chrisengelsma/PolynomialRegression.h
Polynomial regression in c++
#ifndef _POLYNOMIAL_REGRESSION_H
#define _POLYNOMIAL_REGRESSION_H __POLYNOMIAL_REGRESSION_H
/**
* PURPOSE:
*
* Polynomial Regression aims to fit a non-linear relationship to a set of
* points. It approximates this by solving a series of linear equations using
* a least-squares approach.
*
* We can model the expected value y as an nth degree polynomial, yielding
@wolterlw
wolterlw / hand_ssh_anchors.cpp
Created September 20, 2019 19:10
c++ program to get anchors needed for hand detection
/*
parameter JSON
{
"num_layers": 5,
"min_scale": 0.1171875,
"max_scale": 0.75,
"input_size_height": 256,
"input_size_width": 256,
"anchor_offset_x": 0.5,
"anchor_offset_y": 0.5,