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DeniuHe
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np.clip()函数用法
【代码】np.clip()函数用法。原创 2023-10-07 16:24:40 · 186 阅读 · 0 评论 -
Smooth Low Rank and Sparse Matrix Recovery
Smooth Low Rank and Sparse Matrix Recovery原创 2023-06-14 11:09:43 · 139 阅读 · 0 评论 -
SimpleImputer的使用方法
SimpleImputer原创 2022-10-22 16:10:28 · 707 阅读 · 0 评论 -
Dataframe 按条件替换某列中的元素
Dataframe 按条件替换某列中的元素原创 2022-01-13 21:13:59 · 2607 阅读 · 0 评论 -
Dataframe读取行读取列
import numpy as npimport pandas as pddf = pd.read_csv(r"D:\OCdata\ObesityDataSet_raw_and_data_sinthetic.csv")# # -------按列读取# print(df["Gender"])# print(df[["Gender","Age"]])# print(df.loc[:,"Age"])# print(df.loc[:,["Gender","Age"]])## # -------.原创 2022-01-13 20:23:58 · 2646 阅读 · 0 评论 -
Python:逆着遍历一个数组
import numpy as npfor idx in np.arange(0, 10)[::-1]: print(idx)原创 2021-07-01 15:03:55 · 643 阅读 · 0 评论 -
Python:梯度下降实现之小例子
import matplotlib.pyplot as pltimport numpy as npclass GD(object): def __init__(self,seed=None, precision=1.E-6): self.seed = GD.get_seed(seed) # 梯度下降算法的种子点 self.prec = precision # 梯度下降算法的精度 self.path = list() .原创 2021-06-25 10:00:47 · 214 阅读 · 0 评论 -
Python:判断数组中元素是否都满足某条件(比如是否都大于0)
import numpy as npa = np.array([1,2,3,4,5,6])###The first formif a.all() > 0: print("数组中所有元素都大于0")else: print("数据中有小于等于0的元素")###The second formif all(i > 0 for i in a) > 0: print("数组中所有元素都大于0")else: print("数据中有小于等于0的元素").原创 2021-05-12 20:13:32 · 18093 阅读 · 3 评论 -
Python:查看数组中元素是否都满足某一条件(比如是否都大于0)
import numpy as npa = np.array([1,2,3,4,5,6])###The first formif a.all() > 0: print("数组中所有元素都大于0")else: print("数据中有小于等于0的元素")###The second formif all(i > 0 for i in a) > 0: print("数组中所有元素都大于0")else: print("数据中有小于等于0的元素").原创 2021-06-25 09:58:47 · 2917 阅读 · 4 评论 -
对区间样本获取后验估计
if self.intLabeled: for idx in self.intLabeled: interval = deepcopy(self.Xin[idx].inter) print("labels==",self.labels) print("interval===",interval) print("theta===",self.theta) ids_lab = [] for lab in i.原创 2021-04-28 20:12:27 · 172 阅读 · 0 评论 -
Python:学习使用scipy优化工具
单纯形法:import numpy as npfrom scipy.optimize import minimizedef rosen(x): return sum(100.0 * (x[1:] - x[:-1] ** 2.0) ** 2.0 + (1 - x[:-1]) ** 2.0)def callback(xk): print(xk)# 初始迭代点# x0 = np.random.randn(10)*2x0 = np.ones(10)print("x0::",原创 2021-04-22 15:35:35 · 286 阅读 · 0 评论 -
Python:numpy diff() 函数 实现邻行相减 或 邻列相减
import numpy as npA = np.array([[1,2,3],[4,5,6]])print("上面的减去下面的,结果整体少一行:")print(np.diff(A,axis=0))print("右边的减去左边的,结果整体少一列:")print(np.diff(A,axis=1))原创 2021-04-22 09:44:42 · 6352 阅读 · 0 评论 -
Python: numpy tile()函数 可实现ndarray的横向纵向复制
import numpy as npA = np.array([[1,2,3],[4,5,6]])print("把矩阵A先横向复制两次,在整体纵向复制四次:")print(np.tile(A,(2,4)))原创 2021-04-22 09:32:42 · 1194 阅读 · 0 评论 -
Python:矩阵乘法
import numpy as npa = np.array([[1,2,3],[1,2,3]])b = np.array([[1,2,3],[1,2,3]])print(a)print(b)print(a * b)print(a.T @ b)print(a @ b.T)原创 2021-04-21 13:45:30 · 271 阅读 · 0 评论 -
Python:numpy array数据去头去尾巴
拿不准,再试一试 ,刚好用到import numpy as np# def rosen(x):a = np.arange(10)print("a::",a)print("去头",a[1:])print("去尾",a[:-1])原创 2021-04-21 10:41:30 · 1607 阅读 · 0 评论 -
Python: np.where()的使用,注意:它对list列表无效。
x = np.random.randn(4, 4)print(x)A = np.where(x>0, 2, -2)print(A)结果:np.where()对列表无效a = [1,2,2,3,2,5]print(np.where(a == 2))print(np.where(a == 2)[0])结果:a = np.array(a)print(np.where(a == 2))print(np.where(a == 2)[0])...原创 2021-04-21 10:02:44 · 1572 阅读 · 0 评论 -
Python:构建一个半角矩阵(主对角线及以下元素都是1,其他元素都是0)
import numpy as npn_class = 5L = np.zeros((n_class - 1, n_class - 1))print(L)L[np.tril_indices(n_class-1)] = 1.print(L)原创 2021-04-20 20:48:31 · 1791 阅读 · 0 评论 -
Python:获取array或list中的最大值和最小值
第一次发现可以这么用,我好low原创 2021-04-20 20:33:38 · 1224 阅读 · 0 评论 -
Python:如何将numpy array数组中小于0的数替换成0
import numpy as npa = np.array([[0.5,1.5,2.5],[-0.5,0.5,1.5],[-1.5,-0.5,0.5],[-3,-2,-1]])print(a)print(a < 0)##################### a[a<0] = 0# print(a)##################### b = np.where(a>0,a,0)# print(b)#################### np.maximu.原创 2021-04-17 11:04:09 · 10483 阅读 · 0 评论 -
python:将numpy array中的NaN替换为某个数值
import numpy as npa = np.array([[0.5,np.nan,2.5],[-0.5,0.5,1.5],[-1.5,-0.5,0.5],[-3,-2,-1]])print(np.isnan(a))a[np.isnan(a)] = 1.5print(a)原创 2021-04-17 10:49:42 · 5240 阅读 · 0 评论 -
论文词汇:学两个单词 “和谐的Concordant 和 不和谐的discordant“
于是就有了序分了的一个评价指标 :最后一句话讲的非常好!论文出处:Learning to Classify Ordinal Data: The Data Replication MethodJournal of Machine Learning Research 8 (2007) 1393-1429原创 2021-04-14 12:49:23 · 141 阅读 · 0 评论 -
Python:实验中计算各种对方法的在MeanRank/AvgRank的代码
只要结果不要过程!博主懒地写输入。。。不懂啥是mean rank,就没救了~import numpy as npA = [[26.44, 25.8, 25.54, 25.75, 25.32, 26.04, 25.23, 25.11, 24.45],[1.9, 1.88, 4.1, 1.93, 2.88, 2.97, 3.3, 2.96, 1.8],[27.26, 28.39, 28.06, 27.45, 27.67, 30.81, 29.23, 26.62, 26.42],[1.原创 2021-04-13 20:53:02 · 389 阅读 · 0 评论 -
Python:GSx缺点及改进
缺点:大概率首选离群点改进效果:首先剔除密度较小的点,作为虚拟的已标记样本点。粗放版代码:'''author:Danieldate:2021-04-03organization: CQUPTReference: D. Wu, C. Lin, J. Huang. Active learning for regression using greeding sampling. Information Sciences, 2019, 474: 90-105.'''import x.原创 2021-04-03 10:41:08 · 312 阅读 · 0 评论 -
Python:查看数据集信息
import xlwtimport numpy as npimport pandas as pdfrom copy import deepcopyfrom sklearn.metrics import accuracy_score, mean_absolute_errorfrom collections import OrderedDictfrom mord import LogisticATfrom sklearn.model_selection import StratifiedKFol.原创 2021-03-29 11:37:55 · 2967 阅读 · 0 评论 -
Python:实验数据保存
代码存档,读者可以绕道,没有技术内容。import xlrdimport xlwtimport numpy as npfrom pathlib import Pathfrom collections import OrderedDictread_path_1 = Path(r"D:\AOR_experiment\pointwise\uncertainty")read_path_2 = Path(r"D:\AOR_experiment\pointwise\LogitA")read_.原创 2021-03-26 17:09:15 · 666 阅读 · 0 评论 -
Python:使用numpy.outer()函数直接得到一个numpy向量的gram方阵
使用python就是为了节约撸码的时间。import numpy as npfrom sklearn.datasets import load_irisfrom sklearn.metrics.pairwise import rbf_kernelimport pandas as pdfrom scipy.linalg import block_diaga = np.array([1,2,3,4,5])print(np.outer(a,a))###验证b = a.reshap.原创 2021-03-19 22:09:37 · 333 阅读 · 0 评论 -
Python:LogitA
啥也不是import numpy as npimport pandas as pdimport xlwtfrom pathlib import Pathfrom copy import deepcopyfrom collections import OrderedDictfrom sklearn.linear_model import LogisticRegressionfrom sklearn.model_selection import StratifiedKFoldfrom .原创 2021-03-17 11:15:01 · 147 阅读 · 0 评论 -
Python:Generalized Discriminant Analysis (GDA) 手工代码实现 Kernel LDA
"""Auther:Deniu HeDate:2021-03-16"""import numpy as npfrom sklearn.datasets import load_irisfrom sklearn.metrics.pairwise import rbf_kernelimport matplotlib.pyplot as pltfrom scipy.linalg import block_diagclass GDA(): def __init__(self,X,y,g.原创 2021-03-17 10:27:23 · 695 阅读 · 0 评论 -
Python:Kernel based PCA手工代码实现
'''Auther: DeniuHeDate:2021-03-16'''import numpy as npfrom sklearn import datasetsfrom sklearn.metrics.pairwise import rbf_kernelfrom sklearn.decomposition import KernelPCAfrom sklearn.model_selection import train_test_splitimport matplotlib.pypl.原创 2021-03-16 14:53:27 · 404 阅读 · 2 评论 -
Python:数据降序排列索引
ord_ids = np.flipud(np.argsort(self.L))原创 2021-03-16 14:18:32 · 624 阅读 · 0 评论 -
Python:rbf_kernel()径向基核函数 调包法实现
调包偷个懒import numpy as npfrom sklearn.datasets import load_irisfrom sklearn.metrics.pairwise import rbf_kernelimport pandas as pdif __name__ == '__main__': X, y = load_iris(return_X_y=True) a = [1,2,3,4,5,6,7,8] b = [110,111] A = X[.原创 2021-03-15 11:28:47 · 3915 阅读 · 0 评论 -
Python:PCA(principle component analysis)主成分分析手工代码实现
单纯看公式推导看懂了,是没有用的。"""Auther:Deniu HeDate:2021-03-12"""import numpy as npfrom sklearn.datasets import load_irisimport matplotlib.pyplot as pltclass LDA(): def __init__(self,X,y): self.X = X self.y = y self.N = self.X.s.原创 2021-03-15 09:52:40 · 340 阅读 · 0 评论 -
Python:线性判别分析(Linear Discriminant Analysis)手工代码实现
LDA线性判别分析实现有监督降维,代码将iris数据降到2维"""Auther:Deniu HeDate:2021-03-12"""import numpy as npfrom sklearn.datasets import load_irisimport matplotlib.pyplot as pltclass LDA(): def __init__(self,X,y): self.X = X self.y = y s..原创 2021-03-12 12:15:41 · 1810 阅读 · 0 评论 -
Python:numpy 矩阵除以向量
import numpy as npa = np.array([[1,2,3],[1,2,3],[1,2,3],[1,2,3]])b = np.array([1,2,3,4])print(a.shape)c = b.reshape(-1,1)print(c.shape)print(a/c)print(np.sum(a,1))原创 2021-03-02 19:50:46 · 3760 阅读 · 0 评论 -
Latex中的双引号
``$\mathbf{x}_r<_f\mathbf{x}_s$''Tab键上面那个按钮,点两下!原创 2021-01-21 09:28:57 · 1141 阅读 · 0 评论 -
Linear ALeSVM
'''Data: 2021-01-16author: Deniu Heat: CQUPT'''import cvxpy as cpimport xlwtimport numpy as npimport pandas as pdfrom copy import deepcopyfrom sklearn.metrics import accuracy_score, mean_absolute_errorfrom collections import OrderedDictfrom sk.原创 2021-01-16 14:25:13 · 225 阅读 · 0 评论 -
Python: 查看数据集信息
import numpy as npimport pandas as pdfrom pathlib import Patha = [[1,2,3],[4,5,6],[7,8,9]]print(np.mean(a,axis=0))p = Path("D:\OCdata")names = ["Obesity", "PowerPlant-5bin", "PowerPlant-10bin"]for name in names: path = p.joinpath(name + ".cs.原创 2021-01-15 10:08:25 · 2488 阅读 · 1 评论 -
等频装箱
import numpy as npimport pandas as pdpath = r"C:\Users\pc\Desktop\PPT素材\CCPP\ccpp.csv"data = np.array( pd.read_csv(path,header=None))print(data.shape)y = data[:,-1]ord_idx = np.argsort(y)Bins = [1913, 1913, 1914, 1914, 1914]Binss = [1913,3826,574.原创 2021-01-14 13:56:42 · 221 阅读 · 0 评论 -
Python:One-hot-encoding 例子
import pandas as pdimport numpy as npimport osos.getcwd()os.chdir("D:\OCdata")from sklearn.preprocessing import OneHotEncoderfrom sklearn.preprocessing import LabelEncoderdata = pd.read_csv("ObesityDataSet_raw_and_data_sinthetic.csv")# print(dat.原创 2021-01-14 10:38:51 · 573 阅读 · 1 评论 -
Python:自己写的类,声明对象后发现类属性不能自动补全(问题解决)
不能自动补全,可能是因为没有写 self.原创 2021-01-10 16:43:34 · 760 阅读 · 0 评论