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Mastering Development

How to divide an array into a tree of buckets sized by powers of two?

How do you take a number representing a list of items, and divide it into chunks, where the number of chunks is a power-of-two, AND where each chunk also has a power-of-two number of items (where size goes up to a max power of two, so 1, 2, 4, 8, 16, 32, 32 being the […]

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Mastering Development

Find out if there’s equal elements in a list in a column in R

I have a column like: > example [,1] Col.1 "a,b,c,d,e" Col.2 "a,e,d" Col.3 "b,e,f" Col.4 "a,e" Here, a and e is equal, because whenever a appears, e also appears. How can I find this? I tried using duplicate() but it only found "duplicate", not really "equal" elements. > dput(example) structure(c("a,b,c,d,e", "a,e,d", "b,e,f", "a,e"), .Dim = […]

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Linux Mastering Development

How to mount a filesystem in such a way that a specific user has full read access to it?

I want to perform automatic backups of a specific folder, F, in my home directory. To prevent malicious software from removing backups in the repository, however, I have created another user whose sole purpose it is to regularly perform these backups. It has the authority over the repository and obviously needs full read access to […]

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Mastering Development

I am building an ALU in Verilog and my self-checking testbench keeps receiving this continuous blue error?

I am tasked with building an ALU. However, I must not understand how the self-checking testbench with file.tv should run. I have run other simple testbenches just fine. I am sure there is a problem in the way that my testbench module is written, code compiles (using quartus) made a text file with binary and […]

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Mastering Development

Object information does not coincide with Array of Object’s index

I’m trying to get the function infoEst() to iterate over an array of objects and print out the object’s name and location. It iterates fine but it seems like every index in the array is the exact same as the last entry. Am I creating the array of objects incorrectly? import java.util.Scanner; public class Estudiante […]

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Mastering Development

Apply concordance dataframe to zoo objects

I have a zoo object made of several time series, like this: indices <- seq.Date(as.Date(‘2000-01-01’),as.Date(‘2005-01-30’),by="year") a <- zoo(rnorm(5), order.by=indices) b <- zoo(rnorm(5), order.by=indices) c <- zoo(rnorm(5), order.by=indices) ts_origin <- merge(a,b,c) I would like to multiply each zoo series from ts_origin by a ratio contained in a dataframe, an put the results in another zoo object […]

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Ask Engineering

Voltage sensitivity coefficients for unbalanced radial distribution feeders

I am wondering if my implementation of voltage sensitivity coefficients for unbalanced three-phase-four-wire radial distribution feeders is correct. We got \$\bar{V}\$ for phase(s) of all the buses and \$\bar{Y}\$, the admittance matrix of the feeder. \$\mathcal{S}\$ is the set for phases of the slack bus, and \$\mathcal{N}\$ is the set for phase(s) of all the […]

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Mastering Development

TypeError: float() argument must be a string or a number, not ‘method’, [closed]

mavg=mclose.rolling(window=7).mean() dfm = pd.DataFrame (mavg) dfm=dfm.rename(columns={"adjclose":"mavg"}) dfm[‘mavg’]=dfm[‘mavg’].fillna(dfm[‘mavg’].mean) dfm[‘mavg’].dtype dfm[‘mavg’].astype(float) I keep getting an error in the last line Traceback (most recent call last) <ipython-input-173-e3bf956cf99a> in <module> —-> 1 dfm[‘mavg’].astype(float) ~\anaconda3\lib\site-packages\pandas\core\generic.py in astype(self, dtype, copy, errors) 5696 else: 5697 # else, only a single dtype is given -> 5698 new_data = self._data.astype(dtype=dtype, copy=copy, errors=errors) 5699 return […]

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Ask Engineering

Voltage sensitivity coefficients for unbalanced radial distribution feeders

I am wondering if my implementation of voltage sensitivity coefficients for unbalanced three-phase-four-wire radial distribution feeders is correct. We got \$\bar{V}\$ for phase(s) of all the buses and \$\bar{Y}\$, the admittance matrix of the feeder. \$\mathcal{S}\$ is the set for phases of the slack bus, and \$\mathcal{N}\$ is the set for phase(s) of all the […]

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Mastering Development

Save the email ID of the user filling the form

I have a Google Form to collect information from my workers working in remote locations Emp No * Punch * Customer details / mode or travel The data goes into a Google spreadsheet with the below structure Timestamp Emp No Punch Remark Name GeoCode GeoAddress Email I am able to capture the GPS co-ordinates of […]