numpy

Delete a series of elements every nth time in numpy array

你离开我真会死。 提交于 2021-02-16 13:16:46
问题 I know how to delete every 4th element in a numpy array: frame = np.delete(frame,np.arange(4,frame.size,4)) Now I want to know if there is a simple command that can delete every nth (e.g 4) times 3 values. A basic example: input: [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20....] Would lead to: output: [1,2,3,7,8,9,13,14,15,19,20,....] I was hoping for a simple numpy / python functionality, rather than writing a function that has to iterate over the vector (cause it is quite long in my

Delete a series of elements every nth time in numpy array

眉间皱痕 提交于 2021-02-16 13:16:10
问题 I know how to delete every 4th element in a numpy array: frame = np.delete(frame,np.arange(4,frame.size,4)) Now I want to know if there is a simple command that can delete every nth (e.g 4) times 3 values. A basic example: input: [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20....] Would lead to: output: [1,2,3,7,8,9,13,14,15,19,20,....] I was hoping for a simple numpy / python functionality, rather than writing a function that has to iterate over the vector (cause it is quite long in my

numpy memmap memory usage - want to iterate once

为君一笑 提交于 2021-02-16 13:16:04
问题 let say I have some big matrix saved on disk. storing it all in memory is not really feasible so I use memmap to access it A = np.memmap(filename, dtype='float32', mode='r', shape=(3000000,162)) now let say I want to iterate over this matrix (not essentially in an ordered fashion) such that each row will be accessed exactly once. p = some_permutation_of_0_to_2999999() I would like to do something like that: start = 0 end = 3000000 num_rows_to_load_at_once = some_size_that_will_fit_in_memory()

机器学习画图神器来啦!PPT下载!

江枫思渺然 提交于 2021-02-16 02:11:52
↑↑↑点击上方 蓝字 ,回复 资料 ,10个G的惊喜 作者:蛋酱、小舟,编辑:机器之心 神经网络画图神器 ML Visuals 正在持续更新。 去年 5 月,机器之心曾向大家推荐一款名为 ML Visuals 的机器学习画图模板,该项目受到广泛关注,迄今已收获 2.2K Star。ML Visuals 专为解决神经网络画图问题设计,最近,这一模板进行了更新。( 文末附PPT下载链接 ) 项目地址:https://github.com/dair-ai/ml-visuals ML Visuals 现在包含了 100 多个可用的自定义图形,使用者可以在任何论文、博客、PPT 中使用这些资源。 这份 101 页的模板共包含几个部分: 基础组件 架构 机器学习概念 抽象背景 渐变背景 机器学习 & 健康 其他 机器学习系统设计 基础组件 这套画图模板首先提供了多种基础组件,比如表示过程、操作或转换的圆角矩形,表示神经元或任意操作的小圆圈,表示向量的一排小方块以及表示多维数组的网格等。 架构 架构部分的模板数量最多,共有 32 张。对于复杂的模型架构来说,套模板显然事半功倍,比亲手画图要便捷得多。 比如,画出卷积操作的示意图: 使用该模板重现一些经典架构也是得心应手,比如下图是使用该模板绘制的 Transformer 架构图: 机器学习概念 该模板还可以用来表示机器学习中的一些基本概念,比如

Dot product along third axis

青春壹個敷衍的年華 提交于 2021-02-15 13:35:26
问题 I'm trying to take a tensor dot product in numpy using tensordot , but I'm not sure how I should reshape my arrays to achieve my computation. (I'm still new to the mathematics of tensors, in general.) I have arr = np.array([[[1, 1, 1], [0, 0, 0], [2, 2, 2]], [[0, 0, 0], [4, 4, 4], [0, 0, 0]]]) w = [1, 1, 1] And I want to take a dot product along axis=2 , such that I have the matrix array([[3, 0, 6], [0, 12, 0]]) What's the proper numpy syntax for this? np.tensordot(arr, [1, 1, 1], axes=2)

Dot product along third axis

爷,独闯天下 提交于 2021-02-15 13:32:54
问题 I'm trying to take a tensor dot product in numpy using tensordot , but I'm not sure how I should reshape my arrays to achieve my computation. (I'm still new to the mathematics of tensors, in general.) I have arr = np.array([[[1, 1, 1], [0, 0, 0], [2, 2, 2]], [[0, 0, 0], [4, 4, 4], [0, 0, 0]]]) w = [1, 1, 1] And I want to take a dot product along axis=2 , such that I have the matrix array([[3, 0, 6], [0, 12, 0]]) What's the proper numpy syntax for this? np.tensordot(arr, [1, 1, 1], axes=2)

25.conda 下载安装与运用

淺唱寂寞╮ 提交于 2021-02-15 10:00:36
转载: https://www.cnblogs.com/gandoufu/p/9748841.html https://blog.csdn.net/tuzixini/article/details/81560980 1、查看 conda 版本号   conda -V   conda --version 2、conda常用的命令。 1)conda list 查看安装了哪些包。 2)conda env list 或 conda info -e 查看当前存在哪些虚拟环境 3)conda update conda 检查更新当前conda 3、环境管理   3.1、查看当前环境有哪些                conda env list  conda info -e   3.2、查看环境管理的命令帮助              conda env -h   3.3、创建环境                     conda create --name your_env_name      例如:创建 Python 虚拟环境。conda create -n your_env_name python=X.X(2.7、3.6等) anaconda 命令创建python版本为X.X、名字为your_env_name的虚拟环境。your_env

using multiple functions with correlated arrays Numpy Python

陌路散爱 提交于 2021-02-15 07:38:18
问题 The function below is supposed compute either the Uval and Lval functions in accordance to Set and Numbers . For the first two numbers U and 52599 are in relation and L and 52550 are in relation, since the second number has the label L the Lval equation is used. The previous number is function is previous = numbers[1:] and the current function is current = numbers[:-1] . So (52550 - 52599)/52550 * -100 will be the computation for the first two numbers. The equations are supposed to be

using multiple functions with correlated arrays Numpy Python

a 夏天 提交于 2021-02-15 07:37:12
问题 The function below is supposed compute either the Uval and Lval functions in accordance to Set and Numbers . For the first two numbers U and 52599 are in relation and L and 52550 are in relation, since the second number has the label L the Lval equation is used. The previous number is function is previous = numbers[1:] and the current function is current = numbers[:-1] . So (52550 - 52599)/52550 * -100 will be the computation for the first two numbers. The equations are supposed to be

How to implode(reverse of pandas explode) based on a column

点点圈 提交于 2021-02-15 05:53:17
问题 I have a dataframe df like below NETWORK config_id APPLICABLE_DAYS Case Delivery 0 Grocery 5399 SUN 10 1 1 Grocery 5399 MON 20 2 2 Grocery 5399 TUE 30 3 3 Grocery 5399 WED 40 4 I want to implode( combine Applicable_days from multiple rows into single row like below) and get the average case and delivery per config_id NETWORK config_id APPLICABLE_DAYS Avg_Cases Avg_Delivery 0 Grocery 5399 SUN,MON,TUE,WED 90 10 using the groupby on network,config_id i can get the avg_cases and avg_delivery like