在这篇文章中,我们将带领您了解Pythonnumpy模块-npv()实例源码的全貌,包括python中numpy模块的相关情况。同时,我们还将为您介绍有关Jupyter中的Numpy在打印时出错(Py
在这篇文章中,我们将带领您了解Python numpy 模块-npv() 实例源码的全貌,包括python中numpy模块的相关情况。同时,我们还将为您介绍有关Jupyter 中的 Numpy 在打印时出错(Python 版本 3.8.8):TypeError: 'numpy.ndarray' object is not callable、numpy.random.random & numpy.ndarray.astype & numpy.arange、numpy.ravel()/numpy.flatten()/numpy.squeeze()、Numpy:数组创建 numpy.arrray() , numpy.arange()、np.linspace ()、数组基本属性的知识,以帮助您更好地理解这个主题。
本文目录一览:- Python numpy 模块-npv() 实例源码(python中numpy模块)
- Jupyter 中的 Numpy 在打印时出错(Python 版本 3.8.8):TypeError: 'numpy.ndarray' object is not callable
- numpy.random.random & numpy.ndarray.astype & numpy.arange
- numpy.ravel()/numpy.flatten()/numpy.squeeze()
- Numpy:数组创建 numpy.arrray() , numpy.arange()、np.linspace ()、数组基本属性
Python numpy 模块-npv() 实例源码(python中numpy模块)
Python numpy 模块,npv() 实例源码
我们从Python开源项目中,提取了以下20个代码示例,用于说明如何使用numpy.npv()。
- def calc_excel_npv(rate, values):
- orig_npv = np.npv(rate, values)
- excel_npv = orig_npv/(1+rate)
- return excel_npv
- def mirr(values, finance_rate, reinvest_rate):
- """
- Modified internal rate of return.
- Parameters
- ----------
- values : array_like
- Cash flows (must contain at least one positive and one negative
- value) or nan is returned. The first value is considered a sunk
- cost at time zero.
- finance_rate : scalar
- Interest rate paid on the cash flows
- reinvest_rate : scalar
- Interest rate received on the cash flows upon reinvestment
- Returns
- -------
- out : float
- Modified internal rate of return
- """
- values = np.asarray(values, dtype=np.double)
- n = values.size
- pos = values > 0
- neg = values < 0
- if not (pos.any() and neg.any()):
- return np.nan
- numer = np.abs(npv(reinvest_rate, values*pos))
- denom = np.abs(npv(finance_rate, values*neg))
- return (numer/denom)**(1.0/(n - 1))*(1 + reinvest_rate) - 1
- def test_npv(self):
- assert_almost_equal(
- np.npv(0.05, [-15000, 1500, 2500, 3500, 4500, 6000]),
- 122.89, 2)
- def mirr(values, values*neg))
- return (numer/denom)**(1.0/(n - 1))*(1 + reinvest_rate) - 1
- def test_npv(self):
- assert_almost_equal(
- np.npv(0.05, 2)
- def mirr(values, values*neg))
- return (numer/denom)**(1.0/(n - 1))*(1 + reinvest_rate) - 1
- def test_npv(self):
- assert_almost_equal(
- np.npv(0.05, 2)
- def mirr(values, values*neg))
- return (numer/denom)**(1.0/(n - 1))*(1 + reinvest_rate) - 1
- def test_npv(self):
- assert_almost_equal(
- np.npv(0.05, 2)
- def mirr(values, values*neg))
- return (numer/denom)**(1.0/(n - 1))*(1 + reinvest_rate) - 1
- def test_npv(self):
- assert_almost_equal(
- np.npv(0.05, 2)
- def calc_npv(r, ubi, inputs, n):
- x = np.zeros((ubi[''Years Post Transfer''], n))
- y = np.zeros((ubi[''Years Post Transfer''], n))
- # iterate through years of benefits
- for j in range(1, ubi[''Years Post Transfer''] + 1):
- # sum benefits during program
- if(j < r):
- x[j - 1] += ubi[''Expected baseline per capita consumption (nominal USD)'']* \\
- np.power((1.0 + inputs[''UBI''][''Expected annual consumption increase (without the UBI program)'']), float(j))* \\
- inputs[''UBI''][''Work participation adjustment''] + \\
- ubi[''Annual quantity of transfer money used for immediate consumtion (pre-discounting)'']
- # benefits after program
- else:
- x[j - 1] += ubi[''Expected baseline per capita consumption (nominal USD)'']* \\
- np.power((1.0 + inputs[''UBI''][''Expected annual consumption increase (without the UBI program)'']), float(j))
- # investments calculations
- for k in range(n):
- if(j < r + inputs[''UBI''][''Duration of investment benefits (in years) - UBI''][k]):
- x[j - 1][k] += ubi[''Annual return for each year of transfer investments (pre-discounting)''][k]* \\
- np.min([j, inputs[''UBI''][''Duration of investment benefits (in years) - UBI''][k], \\
- r, (inputs[''UBI''][''Duration of investment benefits (in years) - UBI''][k] + r - j)])
- if(j > r):
- x[j - 1][k] += ubi[''Value eventually returned from one years investment (pre-discounting)''][k]
- # log transform and subtact baseline
- y[j - 1] = np.log(x[j - 1])
- y[j - 1] -= np.log(ubi[''Expected baseline per capita consumption (nominal USD)'']* \\
- np.power((1.0 + inputs[''UBI''][''Expected annual consumption increase (without the UBI program)'']), float(j)))
- # npv on yearly data
- z = np.zeros(n)
- for i in range(n):
- z[i] = np.npv(inputs[''Shared''][''discount rate''][i], y[:, i])
- return z
- def mirr(values, values*neg))
- return (numer/denom)**(1.0/(n - 1))*(1 + reinvest_rate) - 1
- def test_npv(self):
- assert_almost_equal(
- np.npv(0.05, 2)
- def npv(rate, values):
- """
- Returns the NPV (Net Present Value) of a cash flow series.
- Parameters
- ----------
- rate : scalar
- The discount rate.
- values : array_like,shape(M,)
- The values of the time series of cash flows. The (fixed) time
- interval between cash flow "events" must be the same as that for
- which `rate` is given (i.e.,if `rate` is per year,then precisely
- a year is understood to elapse between each cash flow event). By
- convention,investments or "deposits" are negative,income or
- "withdrawals" are positive; `values` must begin with the initial
- investment,thus `values[0]` will typically be negative.
- Returns
- -------
- out : float
- The NPV of the input cash flow series `values` at the discount
- `rate`.
- Notes
- -----
- Returns the result of: [G]_
- .. math :: \\\\sum_{t=0}^{M-1}{\\\\frac{values_t}{(1+rate)^{t}}}
- References
- ----------
- .. [G] L. J. Gitman,"Principles of Managerial Finance,Brief," 3rd ed.,
- Addison-Wesley,2003,pg. 346.
- Examples
- --------
- >>> np.npv(0.281,[-100,39,59,55,20])
- -0.0084785916384548798
- (Compare with the Example given for numpy.lib.financial.irr)
- """
- values = np.asarray(values)
- return (values / (1+rate)**np.arange(0, len(values))).sum(axis=0)
- def npv(rate, len(values))).sum(axis=0)
- def npv(rate, len(values))).sum(axis=0)
- def npv(rate, len(values))).sum(axis=0)
- def npv(rate, len(values))).sum(axis=0)
- def npv(rate, len(values))).sum(axis=0)
Jupyter 中的 Numpy 在打印时出错(Python 版本 3.8.8):TypeError: 'numpy.ndarray' object is not callable
如何解决Jupyter 中的 Numpy 在打印时出错(Python 版本 3.8.8):TypeError: ''numpy.ndarray'' object is not callable?
晚安, 尝试打印以下内容时,我在 jupyter 中遇到了 numpy 问题,并且得到了一个 错误: 需要注意的是python版本是3.8.8。 我先用 spyder 测试它,它运行正确,它给了我预期的结果
使用 Spyder:
import numpy as np
for i in range (5):
n = np.random.rand ()
print (n)
Results
0.6604903457995978
0.8236300859753154
0.16067650689842816
0.6967868357083673
0.4231597934445466
现在有了 jupyter
import numpy as np
for i in range (5):
n = np.random.rand ()
print (n)
-------------------------------------------------- ------
TypeError Traceback (most recent call last)
<ipython-input-78-0c6a801b3ea9> in <module>
2 for i in range (5):
3 n = np.random.rand ()
----> 4 print (n)
TypeError: ''numpy.ndarray'' object is not callable
感谢您对我如何在 Jupyter 中解决此问题的帮助。
非常感谢您抽出宝贵时间。
阿特,约翰”
解决方法
暂无找到可以解决该程序问题的有效方法,小编努力寻找整理中!
如果你已经找到好的解决方法,欢迎将解决方案带上本链接一起发送给小编。
小编邮箱:dio#foxmail.com (将#修改为@)
numpy.random.random & numpy.ndarray.astype & numpy.arange
今天看到这样一句代码:
xb = np.random.random((nb, d)).astype(''float32'') #创建一个二维随机数矩阵(nb行d列)
xb[:, 0] += np.arange(nb) / 1000. #将矩阵第一列的每个数加上一个值
要理解这两句代码需要理解三个函数
1、生成随机数
numpy.random.random(size=None)
size为None时,返回float。
size不为None时,返回numpy.ndarray。例如numpy.random.random((1,2)),返回1行2列的numpy数组
2、对numpy数组中每一个元素进行类型转换
numpy.ndarray.astype(dtype)
返回numpy.ndarray。例如 numpy.array([1, 2, 2.5]).astype(int),返回numpy数组 [1, 2, 2]
3、获取等差数列
numpy.arange([start,]stop,[step,]dtype=None)
功能类似python中自带的range()和numpy中的numpy.linspace
返回numpy数组。例如numpy.arange(3),返回numpy数组[0, 1, 2]
numpy.ravel()/numpy.flatten()/numpy.squeeze()
numpy.ravel(a, order=''C'')
Return a flattened array
numpy.chararray.flatten(order=''C'')
Return a copy of the array collapsed into one dimension
numpy.squeeze(a, axis=None)
Remove single-dimensional entries from the shape of an array.
相同点: 将多维数组 降为 一维数组
不同点:
ravel() 返回的是视图(view),意味着改变元素的值会影响原始数组元素的值;
flatten() 返回的是拷贝,意味着改变元素的值不会影响原始数组;
squeeze()返回的是视图(view),仅仅是将shape中dimension为1的维度去掉;
ravel()示例:
1 import matplotlib.pyplot as plt
2 import numpy as np
3
4 def log_type(name,arr):
5 print("数组{}的大小:{}".format(name,arr.size))
6 print("数组{}的维度:{}".format(name,arr.shape))
7 print("数组{}的维度:{}".format(name,arr.ndim))
8 print("数组{}元素的数据类型:{}".format(name,arr.dtype))
9 #print("数组:{}".format(arr.data))
10
11 a = np.floor(10*np.random.random((3,4)))
12 print(a)
13 log_type(''a'',a)
14
15 a1 = a.ravel()
16 print("a1:{}".format(a1))
17 log_type(''a1'',a1)
18 a1[2] = 100
19
20 print(a)
21 log_type(''a'',a)
flatten()示例
1 import matplotlib.pyplot as plt
2 import numpy as np
3
4 def log_type(name,arr):
5 print("数组{}的大小:{}".format(name,arr.size))
6 print("数组{}的维度:{}".format(name,arr.shape))
7 print("数组{}的维度:{}".format(name,arr.ndim))
8 print("数组{}元素的数据类型:{}".format(name,arr.dtype))
9 #print("数组:{}".format(arr.data))
10
11 a = np.floor(10*np.random.random((3,4)))
12 print(a)
13 log_type(''a'',a)
14
15 a1 = a.flatten()
16 print("修改前a1:{}".format(a1))
17 log_type(''a1'',a1)
18 a1[2] = 100
19 print("修改后a1:{}".format(a1))
20
21 print("a:{}".format(a))
22 log_type(''a'',a)
squeeze()示例:
1. 没有single-dimensional entries的情况
1 import matplotlib.pyplot as plt
2 import numpy as np
3
4 def log_type(name,arr):
5 print("数组{}的大小:{}".format(name,arr.size))
6 print("数组{}的维度:{}".format(name,arr.shape))
7 print("数组{}的维度:{}".format(name,arr.ndim))
8 print("数组{}元素的数据类型:{}".format(name,arr.dtype))
9 #print("数组:{}".format(arr.data))
10
11 a = np.floor(10*np.random.random((3,4)))
12 print(a)
13 log_type(''a'',a)
14
15 a1 = a.squeeze()
16 print("修改前a1:{}".format(a1))
17 log_type(''a1'',a1)
18 a1[2] = 100
19 print("修改后a1:{}".format(a1))
20
21 print("a:{}".format(a))
22 log_type(''a'',a)
从结果中可以看到,当没有single-dimensional entries时,squeeze()返回额数组对象是一个view,而不是copy。
2. 有single-dimentional entries 的情况
1 import matplotlib.pyplot as plt
2 import numpy as np
3
4 def log_type(name,arr):
5 print("数组{}的大小:{}".format(name,arr.size))
6 print("数组{}的维度:{}".format(name,arr.shape))
7 print("数组{}的维度:{}".format(name,arr.ndim))
8 print("数组{}元素的数据类型:{}".format(name,arr.dtype))
9 #print("数组:{}".format(arr.data))
10
11 a = np.floor(10*np.random.random((1,3,4)))
12 print(a)
13 log_type(''a'',a)
14
15 a1 = a.squeeze()
16 print("修改前a1:{}".format(a1))
17 log_type(''a1'',a1)
18 a1[2] = 100
19 print("修改后a1:{}".format(a1))
20
21 print("a:{}".format(a))
22 log_type(''a'',a)
Numpy:数组创建 numpy.arrray() , numpy.arange()、np.linspace ()、数组基本属性
一、Numpy数组创建
part 1:np.linspace(起始值,终止值,元素总个数
import numpy as np
''''''
numpy中的ndarray数组
''''''
ary = np.array([1, 2, 3, 4, 5])
print(ary)
ary = ary * 10
print(ary)
''''''
ndarray对象的创建
''''''
# 创建二维数组
# np.array([[],[],...])
a = np.array([[1, 2, 3, 4], [5, 6, 7, 8]])
print(a)
# np.arange(起始值, 结束值, 步长(默认1))
b = np.arange(1, 10, 1)
print(b)
print("-------------np.zeros(数组元素个数, dtype=''数组元素类型'')-----")
# 创建一维数组:
c = np.zeros(10)
print(c, ''; c.dtype:'', c.dtype)
# 创建二维数组:
print(np.zeros ((3,4)))
print("----------np.ones(数组元素个数, dtype=''数组元素类型'')--------")
# 创建一维数组:
d = np.ones(10, dtype=''int64'')
print(d, ''; d.dtype:'', d.dtype)
# 创建三维数组:
print(np.ones( (2,3,4), dtype=np.int32 ))
# 打印维度
print(np.ones( (2,3,4), dtype=np.int32 ).ndim) # 返回:3(维)
结果图:
part 2 :np.linspace ( 起始值,终止值,元素总个数)
import numpy as np
a = np.arange( 10, 30, 5 )
b = np.arange( 0, 2, 0.3 )
c = np.arange(12).reshape(4,3)
d = np.random.random((2,3)) # 取-1到1之间的随机数,要求设置为诶2行3列的结构
print(a)
print(b)
print(c)
print(d)
print("-----------------")
from numpy import pi
print(np.linspace( 0, 2*pi, 100 ))
print("-------------np.linspace(起始值,终止值,元素总个数)------------------")
print(np.sin(np.linspace( 0, 2*pi, 100 )))
结果图:
二、Numpy的ndarray对象属性:
数组的结构:array.shape
数组的维度:array.ndim
元素的类型:array.dtype
数组元素的个数:array.size
数组的索引(下标):array[0]
''''''
数组的基本属性
''''''
import numpy as np
print("--------------------案例1:------------------------------")
a = np.arange(15).reshape(3, 5)
print(a)
print(a.shape) # 打印数组结构
print(len(a)) # 打印有多少行
print(a.ndim) # 打印维度
print(a.dtype) # 打印a数组内的元素的数据类型
# print(a.dtype.name)
print(a.size) # 打印数组的总元素个数
print("-------------------案例2:---------------------------")
a = np.array([[1, 2, 3], [4, 5, 6]])
print(a)
# 测试数组的基本属性
print(''a.shape:'', a.shape)
print(''a.size:'', a.size)
print(''len(a):'', len(a))
# a.shape = (6, ) # 此格式可将原数组结构变成1行6列的数据结构
# print(a, ''a.shape:'', a.shape)
# 数组元素的索引
ary = np.arange(1, 28)
ary.shape = (3, 3, 3) # 创建三维数组
print("ary.shape:",ary.shape,"\n",ary )
print("-----------------")
print(''ary[0]:'', ary[0])
print(''ary[0][0]:'', ary[0][0])
print(''ary[0][0][0]:'', ary[0][0][0])
print(''ary[0,0,0]:'', ary[0, 0, 0])
print("-----------------")
# 遍历三维数组:遍历出数组里的每个元素
for i in range(ary.shape[0]):
for j in range(ary.shape[1]):
for k in range(ary.shape[2]):
print(ary[i, j, k], end='' '')
结果图:
我们今天的关于Python numpy 模块-npv() 实例源码和python中numpy模块的分享已经告一段落,感谢您的关注,如果您想了解更多关于Jupyter 中的 Numpy 在打印时出错(Python 版本 3.8.8):TypeError: 'numpy.ndarray' object is not callable、numpy.random.random & numpy.ndarray.astype & numpy.arange、numpy.ravel()/numpy.flatten()/numpy.squeeze()、Numpy:数组创建 numpy.arrray() , numpy.arange()、np.linspace ()、数组基本属性的相关信息,请在本站查询。
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