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Questions tagged [exp]

The Exponential - aka exp(x) function

The vast majority of the 21 posts tagged [exp] relate to the Exponential function i.e. f(x) = e^x where e is the number which is approximately 2.71828. This function is very important in statistics and many other fields.

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How to plot exp-functions using r

I want to plot two e-functions (in a single graph) using R: a) f(t)=20(1-e^(-0,1t)) b) f(t)=0,4t(t+7)e^(-0,1t) I tried the curve() function but I don't know how to use it with e-functions. Could you help me please? Thanks!
afiw
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Math.exp in Java calculates incorrectly?

In Javascript, I tried Math.exp(-1800/2000) and the result is 0.4065696597405991. However, in Java, the same function returns 1.0? I read the documentations and Math.exp in Java and Javascript basically do the same thing. In Java, Math.exp(a)…
phuwin
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Handling large numbers and precision of Ricean Fading PDF python

I'm trying to calculate Ricean Fading PDF using following equation. RIcean Fading PDF. where 'y' is normalized envelope and 'gamma' is SNR if the K value is large, then math.exp(-((1.+_gamma)*pow(_y,2.) + _gamma)) exp results in big floating point…
LO_py
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Cron does not run shell script properly

im having the problem that a bash script is not running from cron. When i instead run it as root from the cli it works well. As you can see i write to a txt file when the script has finished. This is also done when the script runs from cron, only…
helmut1978
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approximate summation of exponential function in python

I wish to find the approximate sum of exponential function , my code looks like this: import numpy as np import matplotlib.pyplot as plt import math N = input ("Please enter an integer at which term you want to turncate your summation") x = input…
bhjghjh
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IEEE-754 double precision and splitting method

When you compute elementary functions, you apply constant modification. Specially in the implementation of exp(x). In all these implementations any correction with ln(2) is done in two steps. ln(2) is split in two numbers: static const double ln2p1 …
Timocafé
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export and import to different tablespace

I am after doing an export from a tablespace and then importing it into a different tablespace. However i cannot use datapump as i want to do an export into my local pc and then import it from my local drive: as it stands i am using the following…
CBR
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plotting of graph with unknown parameter containing exp

Equation is as shown: Ii=7.5-1.1e-06*exp((Vv+0.3*Ii)/2)+(1.1e-06)-(Vv+0.3*Ii)/271; How can I plot a graph of Ii vs Vv, given Vv with a step size of: Vv=0:1.5:35; Would really appreciate any help thanks
user5850017
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how to tackle Matlab error in calculation of exp?

I have to calculate the angle of complex summations like (exp(1i*0)+exp(1i*2*pi/3)+exp(1i*-2*pi/3)) which is equal to (exp(1i*0)+exp(1i*2*pi/3)+exp(1i*4*pi/3)) but the results are different! because of the precision of exp matlab function. ans = …
user3806654
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Factor symbolic expression involving exp()

I have a symbolic function exp(a+b), and would like to factor out A=exp(a) to produce exp(a+b) = A*exp(b), but I cannot figure out how to do this in MATLAB. Below is my attempt: syms a b A X = exp(a+b); Y = subs(X,exp(a),A) % = A*exp(b) however, Y…
pdwhoward
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expm1 for GNU gfortran

Is there any way to call a fast implementation of expm1 from GNU Fortran? Ideally, it would be great to have a function to calculate (exp(x)-1)/x directly to avoid extra check for zero argument. Elemental version of expm1 would be especially…
Roux
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Matlab exp produces unexpected result

As a Matlab-noob i've been experimenting a bit with the exp-function. What I found was that putting: a = 1.1 b = 5 test = exp (a+b) produced the desired (correct) answer. (test = 445.8578) However: replacing a with a matrix gave completely the…
Razoredge
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Power function for real base and real exponent

I need to write a power function in Python which works with real base and real exponent. a^b && a,b ∈ R I'm stuck at this point: def power_real_numbers(base, exp): if isinstance(exp, int): return power_bin_recursive(base, exp) …
TheRetardedOne
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Having issues in QT Creator trying to make an exponential equation

I am new to QT Creator and my knowledge of C++ is still beginner so I am running into some issues. I am trying to make a program that calculates a formula about bacteria growth. I am trying to type the equivalent of "e^kt"(k and t being variables…
ptrauth
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Java recursion – exponentiation method

I made the method exp in java but when I process the method I always get the same answer public class Recursion { private double x; private int n; // Method exp(x,n) public static double exp(double x,int n){ if(n >…
Samara92
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