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Questions tagged [exponential]

Exponential can refer to a mathematics function, a curve / graph / dataset that follows the growth of that function, the exponential distribution in statistics, or a format to represent floats.

Exponential can refer to a mathematics function, a curve / graph / dataset that follows the growth of that function, the exponential distribution in statistics, or a format to represent floats.

Definitions from wikipedia:

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Calculating exponential growth equation from data points c#

I am trying to analyse some data using a C# app and need to calculate trend lines. I am aware that there are multiple types of trend line but for now I am trying to calculate exponential growth; I am going to be using it to predict future values.…
manicmonkey21421
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Calculating Exponential Moving Average using Esper

Looking for a way to calculate the Exponential Moving Average over a window of 5 EMA5 and EMA20 using Esper (EPL) statements. I have a stream of priceEvent (timeStamp , symbol and price) coming in and I wrote a Simple moving avrage SMA over a…
tradetronics
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Displaying 6.5235375356299998e-07 without exponential notation

I have to convert exponential strings, like 6.5235375356299998e-07, to a float value, and display the result of my computation like 0.00000065235... How can I do this in a Python program?
StefanS
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How to find the Longest Common Subsequence in Exponential time?

I can do this the proper way using dynamic programming but I can't figure out how to do it in exponential time. I'm looking to find the largest common sub-sequence between two strings. Note: I mean subsequences and not sub-strings the symbols that…
Declan McKenna
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How can I do exponential regression in Javascript?

can someone tell me how to do exponential regression or point me to a good explaination? I want to implement it in a javascript tool. I know that theoretically, I have to create a discrepancy function, take its first derivation, set it equal to zero…
thejh
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How to generate a negative exponential distribution in R

I was manually creating a negative exponent distribution today and was trying to figure out a faster/easier solution. First, I just manually crafted a geometric sequence such as this one, multiplying constantly by .60 til I neared zero: x <-…
Shawn Hemelstrand
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How do I fit an exponential decay curve which accounts for uncertainties?

I have some radioactive decay data, which has uncertainties in both x and y. The graph itself is all good to go, but I need to plot the exponential decay curve and return the report from the fitting, to find the half-life, and reduced chi^2. The…
Epideme
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Can't calculate e^(-x) for "high" x

This is my code: def fact(y): if y == 0: fact=1 return fact else: fact=1 for k in range (1, y+1): fact = fact * k return fact def e_negative_x(x): n=0 numerical_precesion=1 …
Miguel Godinho
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python SciPy curve_fit with np.exp returns with pcov = inf

I'm trying to optimize a exponential fitting with scipy.optimize.curve_fit. But the result is no good . My code is : def func(x, a, b, c): return a * np.exp(-b * x) + c # xdata and data is obtain from another dataframe and their type is…
Wenjing Li
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How to do exponentiation e when 'e' is decimal for very large numbers of e?

Say, base = 2 and e = 20000.5671 How to perform (base power e) for above example in java. Clearly Math.pow(base, e) is not the way to go as it print's "Infinity" and BigDecimal accepts 'e' of type int only. Any other way to achieve this? Expecting…
user12318711
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Estimating parameters of exponential decay model where DVs are dependent on sum of different time-series in R

I would like to know how to proceed with the following non linear regression analysis, which is a simplified version of my real problem. 5 Participants where asked to observe the speed of three different cars: Audis, VWs and Porsches over a ten…
Jj Blevins
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Exponential Shorthand for Integers

So my understanding is that this: 1e3 Equates to 1000.0. My question is, is there a similar shorthand for integers? I realize that I can do: static_cast(1e3). Is there anything available to me outside of this?
Jonathan Mee
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Curve fit exponential growth function in Python

I have the following data points that I would like to curve fit: import matplotlib.pyplot as plt import numpy as np from scipy.optimize import curve_fit t = np.array([15474.6, 15475.6, 15476.6, 15477.6, 15478.6, 15479.6, 15480.6, …
wigging
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x87 FPU computing e powered x, maybe with a Taylor series?

I am trying to compute the function e^x (x is a single-precision float) in x87. To achieve this I am using the Taylor-series (as a reminder: e^x = 1 + (x^1)/1! + (x^2)/2! + ... + (x^n)/n!) As I'm working with the x87, I can calculate all values in…
Maru
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numpy.exponential slightly different behaviour

I have installed Python3.6, distribution Anaconda, in two different machines. I cannot swear that I used the same installer file, although I think I did. I see the same when I try to check the Python, Anaconda and numpy versions: I was getting…
zeycus
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