Function - Compilation error. Line 9: no viable alternative at character '{' - function

I am trying to write a trading strategy in Pine Script, but I am getting a compilation error on line 9. The error message states that there is "no viable alternative at character '{'". I have tried adding the keyword "function" before the function name, but the error still persists. The goal is to have the code look at the volatility of the market with MACD, 200 EMA and overall volume with in an hour to determine a safe amount to invest during that period. Can someone please help me fix this error and make my code compile successfully?
function calcTradeAmount(v) => {
tradeAmount = money * (v / 100)
return tradeAmount
}
If the function works properly my if(long) and if(shorts) should be able to pull a different number each time. I don't want to have 1 trade be the entire portfolio each time.
Sample:
if (long)
tradeAmount = calcTradeAmount(volatility)
entryPrice = low

calcTradeAmount(v) =>
tradeAmount = money * (v / 100)
tradeAmount

Related

Result of user-defined function not displaying on web app

I am trying to define a function that divides Amount of money by Number of days.
So far the user can submit values, but I don't know how to make the result display on my Streamlit web app.
I copied part of my code below.
P.S. I am also a complete beginner in Python.
Thanks for any help
#HOW OFTEN EAT OUT
st.write("2. How often do you eat out?")
form04 = st.form(key='form04')
days = form04.text_input('Please enter average number of days')
submit04 = form04.form_submit_button('Submit')
#HOW MUCH INCOME
if submit04:
st.write('3. What is your monthly income?')
form05 = st.form(key='form05')
income = form05.text_input('Please enter monthly income')
submit05 = form05.form_submit_button('Submit')
if submit05:
def idealbudget(days, income):
budget=float(income)/float(days)
return float(budget)
st.write('Result is', budget)
In this code snippet, you define a function but you never actually call it:
if submit05:
def idealbudget(days, income):
budget=float(income)/float(days)
return float(budget)
st.write('Result is', budget)
Additionally, your st.write call is tabbed incorrectly, it should be at the same level as the def statement. A working solution probably looks like the following (untested):
if submit05:
def idealbudget(days, income):
budget=float(income)/float(days)
return float(budget)
st.write('Result is', idealbudget(days, income))

Sentence-count function not returning total count

So i've been trying to create a sentence-count function which will cycle through the following 'story':
let story = 'Last weekend, I took literally the most beautiful bike ride of my life. The route is called "The 9W to Nyack" and it actually stretches all the way from Riverside Park in Manhattan to South Nyack, New Jersey. It\'s really an adventure from beginning to end! It is a 48 mile loop and it basically took me an entire day. I stopped at Riverbank State Park to take some extremely artsy photos. It was a short stop, though, because I had a really long way left to go. After a quick photo op at the very popular Little Red Lighthouse, I began my trek across the George Washington Bridge into New Jersey. The GW is actually very long - 4,760 feet! I was already very tired by the time I got to the other side. An hour later, I reached Greenbrook Nature Sanctuary, an extremely beautiful park along the coast of the Hudson. Something that was very surprising to me was that near the end of the route you actually cross back into New York! At this point, you are very close to the end.';
And I realise the problem I'm having but I cannot find a way around this. Basically I want my code to return a the total sCount below but seeing as I've returned my sCount after my loop, it's only adding and returning the one count as a total:
const sentenceTotal = (word) => {
let sCount = 0;
if (word[word.length-1] === "." || word[word.length-1] === "!" || word[word.length-1] === "?") {
sCount += 1;
};
return sCount;
};
// console.log(sentenceTotal(story)) returns '1'.
I've tried multiple ways around this, such as returning sentenceTotal(word) instead of sCount but console.log will just log the function name.
I can make it return the correct sCount total if I remove the function element of it, but that's not what I want.
I don't see any loop or iterator which would go through story to count the number of occurrences of ., ?, or !.
Having recently tackled "counting sentences" myself I know it is a non-trivial problem with many edge cases.
For a simple use-case though you can use split and a regular expression;
story.split(/[?!.]/).length
So you could wrap that in your function like so:
const sentenceTotal = (word) => {
return word.split(/[?.!]/).length
};
let story = 'Last weekend, I took literally the most beautiful bike ride of my life. The route is called "The 9W to Nyack" and it actually stretches all the way from Riverside Park in Manhattan to South Nyack, New Jersey. It\'s really an adventure from beginning to end! It is a 48 mile loop and it basically took me an entire day. I stopped at Riverbank State Park to take some extremely artsy photos. It was a short stop, though, because I had a really long way left to go. After a quick photo op at the very popular Little Red Lighthouse, I began my trek across the George Washington Bridge into New Jersey. The GW is actually very long - 4,760 feet! I was already very tired by the time I got to the other side. An hour later, I reached Greenbrook Nature Sanctuary, an extremely beautiful park along the coast of the Hudson. Something that was very surprising to me was that near the end of the route you actually cross back into New York! At this point, you are very close to the end.';
sentenceTotal(story)
=> 13
There a several strange things about you question so I'll do it in 3 steps :
First step : The syntax.
What you wrote is the assignement to a const of an anonymous variable. So what it does is :
Create a const name 'sentenceCount'
To this const, assign the anonymous function (words) => {...}
Now you have this : sentenceCount(words){...}
And that's all. Because what you wrote : ()=>{} is not the calling of a function, but the declaration of an anonym function, you should read this : https://www.w3schools.com/js/js_function_definition.asp
If you want a global total, you must have a global total variable(not constant) so that the total isn't lost. So :
let sCount = 0; //<-- have sCount as a global variable not a const
function isEndOfSentence(word) {
if (word[word.length-1] === "." || word[word.length-1] === "!" || word[word.length-1] === "?") {
sCount += 1;
};
};
If you are forbidden from using a global variable (and it's best to not do so), then you have to register the total as a return of your function and store the total in the calling 'CountWords(sentence)' function.
function isEndOfSentence(words) {...}
callingFunction(){
//decalaration
let total;
//...inside your loop
total += isEndOfSentence(currentWord)
}
The algorithm
Can you provide more context as how you use you function ?
If your goal is to count the words until there is a delimiter to mark the end of a sentence, your function will not be of great usage .
As it is written, your function will only ever be able to return 0 or 1. As it does the following :
The function is called.
It create a var called sCount and set it to 0
It increment or not sCount
It return sCount so 1 or 0
It's basically a 'isEndOfSentence' function that would return a boolean. It's usage should be in an algorithm like :
// var totalSentence = 0
// for each word
// if(isEndOfSentence(word))
// totalSentence + totalSentence = 1
// endfor
Also this comes back to just counting the punctuation to count the number of sentence.
The quick and small solution
Also I tried specifically to keep the program in an algorithm explicit form since I guess that's what you're dealing with.
But I feel that you wanted to write something small and with as little characters as possible so for your information, there are faster way of doing this with a tool called regex and the native JS 'split(separator)' function of a string.
A regex is a description of a string that it can match to and when used can return those match. And it can be used in JS to split a string:
story.split(/[?!.]/) //<-- will return an array of the sentences of your story.
story.split(/[?!.]/).length //<-- will return the number of element of the array of the sentences of your story, so the sentence count
That does what you wanted but with one line of code. But If you want to be smart about you problem, remember that I said
Also this comes back to just counting the punctuation to count the number of sentence.
So we'll just do that right ?
story.match(/(\.\.\.)|[.?!]/g).length
Have fun here ;) : https://regexr.com/
I hope that helps you ! Good luck !

Ruby Geocoder near working unexpectedly

Using Alex Reisner's Ruby Geocoder, I have a model "Spot" which is geocoded using this gem
If I select the first spot into and object:
s = Spot.first
Then try to find all the spots within a 10 mile radius (let's say there should be 12 of them), then i would expect Spot.near(s,10) to return an active record object containing 12 spots. Instead it's just returning something like this every time:
Spot.near(s1,10)
=> {:select=>"spots.*, AS distance, CAST(DEGREES(ATAN2( RADIANS(spots.longitude - -6.88671972656243), RADIANS(spots.latitude - 55.1729431175342))) + 360 AS decimal) % 360 AS bearing", :conditions=>["spots.latitude BETWEEN 55.028211334423354 AND 55.31767490064505 AND spots.longitude BETWEEN -7.140145500612388 AND -6.633293952512472 AND <= ?", 10], :order=>"distance ASC"}
Basically it's returning some SQL but no results.
What's going wrong here? Even if i try something a lot wider, like:
Spot.near([40,0],10000)
I still basically get no results back...
EDIT
I am able to execute the query using this (not pretty) addition...
q = Spot.near(s1,10)
spots = Spot.select(q[:select]).where(q[:conditions]).order(q[:order])

How do I set a function to a variable in MATLAB

As a homework assignment, I'm writing a code that uses the bisection method to calculate the root of a function with one variable within a range. I created a user function that does the calculations, but one of the inputs of the function is supposed to be "fun" which is supposed to be set equal to the function.
Here is my code, before I go on:
function [ Ts ] = BisectionRoot( fun,a,b,TolMax )
%This function finds the value of Ts by finding the root of a given function within a given range to a given
%tolerance, using the Bisection Method.
Fa = fun(a);
Fb = fun(b);
if Fa * Fb > 0
disp('Error: The function has no roots in between the given bounds')
else
xNS = (a + b)/2;
toli = abs((b-a)/2);
FxNS = fun(xns);
if FxNS == 0
Ts = xNS;
break
end
if toli , TolMax
Ts = xNS;
break
end
if fun(a) * FxNS < 0
b = xNS;
else
a = xNS;
end
end
Ts
end
The input arguments are defined by our teacher, so I can't mess with them. We're supposed to set those variables in the command window before running the function. That way, we can use the program later on for other things. (Even though I think fzero() can be used to do this)
My problem is that I'm not sure how to set fun to something, and then use that in a way that I can do fun(a) or fun(b). In our book they do something they call defining f(x) as an anonymous function. They do this for an example problem:
F = # (x) 8-4.5*(x-sin(x))
But when I try doing that, I get the error, Error: Unexpected MATLAB operator.
If you guys want to try running the program to test your solutions before posting (hopefully my program works!) you can use these variables from an example in the book:
fun = 8 - 4.5*(x - sin(x))
a = 2
b = 3
TolMax = .001
The answer the get in the book for using those is 2.430664.
I'm sure the answer to this is incredibly easy and straightforward, but for some reason, I can't find a way to do it! Thank you for your help.
To get you going, it looks like your example is missing some syntax. Instead of either of these (from your question):
fun = 8 - 4.5*(x - sin(x)) % Missing function handle declaration symbol "#"
F = # (x) 8-4.5*(x-sin9(x)) %Unless you have defined it, there is no function "sin9"
Use
fun = #(x) 8 - 4.5*(x - sin(x))
Then you would call your function like this:
fun = #(x) 8 - 4.5*(x - sin(x));
a = 2;
b = 3;
TolMax = .001;
root = BisectionRoot( fun,a,b,TolMax );
To debug (which you will need to do), use the debugger.
The command dbstop if error stops execution and opens the file at the point of the problem, letting you examine the variable values and function stack.
Clicking on the "-" marks in the editor creates a break point, forcing the function to pause execution at that point, again so that you can examine the contents. Note that you can step through the code line by line using the debug buttons at the top of the editor.
dbquit quits debug mode
dbclear all clears all break points

Passing variables into a function in Lua

I'm new to Lua, so (naturally) I got stuck at the first thing I tried to program. I'm working with an example script provided with the Corona Developer package. Here's a simplified version of the function (irrelevant material removed) I'm trying to call:
function new( imageSet, slideBackground, top, bottom )
function g:jumpToImage(num)
print(num)
local i = 0
print("jumpToImage")
print("#images", #images)
for i = 1, #images do
if i < num then
images[i].x = -screenW*.5;
elseif i > num then
images[i].x = screenW*1.5 + pad
else
images[i].x = screenW*.5 - pad
end
end
imgNum = num
initImage(imgNum)
end
end
If I try to call that function like this:
local test = slideView.new( myImages )
test.jumpToImage(2)
I get this error:
attempt to compare number with nil
at line 225. It would seem that "num" is not getting passed into the function. Why is this?
Where are you declaring g? You're adding a method to g, which doesn't exist (as a local). Then you're never returning g either. But most likely those were just copying errors or something. The real error is probably the notation that you're using to call test:jumpToImage.
You declare g:jumpToImage(num). That colon there means that the first argument should be treated as self. So really, your function is g.jumpToImage(self, num)
Later, you call it as test.jumpToImage(2). That makes the actual arguments of self be 2 and num be nil. What you want to do is test:jumpToImage(2). The colon there makes the expression expand to test.jumpToImage(test, 2)
Take a look at this page for an explanation of Lua's : syntax.