For Loop and Sum
$begingroup$
I am requested to do a sum of the first fifty positive even numbers by using For
loop.
The For
loop that I created is
For[natNum = 2, natNum <= 50, natNum = natNum + 2, Print[natNum]]
The output of this is a list of numbers from 2 to 50 and they are increasing by 2. Now I need these numbers to be sum so I created
Sum[For[natNum = 2, natNum <= 50, natNum = natNum + 2, Print[natNum]]]
However, it is not a correct input. I am not sure if I should write the Sum
inside the For
loop.
homework
$endgroup$
add a comment |
$begingroup$
I am requested to do a sum of the first fifty positive even numbers by using For
loop.
The For
loop that I created is
For[natNum = 2, natNum <= 50, natNum = natNum + 2, Print[natNum]]
The output of this is a list of numbers from 2 to 50 and they are increasing by 2. Now I need these numbers to be sum so I created
Sum[For[natNum = 2, natNum <= 50, natNum = natNum + 2, Print[natNum]]]
However, it is not a correct input. I am not sure if I should write the Sum
inside the For
loop.
homework
$endgroup$
3
$begingroup$
If this is a class assignment, I'd suggest withdrawing from the class.For
loops are almost never a good way to do anything in Mathematica.
$endgroup$
– John Doty
3 hours ago
$begingroup$
If you want the first 50 positive even numbers, I believe that is {2, 4, ..., 100}. The sum is (2+100) + (4+98) + ... + (50 + 52) = 102 * 25 = 2550.
$endgroup$
– mjw
2 hours ago
$begingroup$
Total@Range[2, 2*50, 2]
would be pretty direct. Note also thatPrint
prints its arguments, but does not return them (in fact, it returnsNull
).
$endgroup$
– MarcoB
1 hour ago
2
$begingroup$
Since the days of Carl Friedrich Gauß we know that using aFor
loop to compute50 * 51
is a pretty bad idea....
$endgroup$
– Henrik Schumacher
35 mins ago
add a comment |
$begingroup$
I am requested to do a sum of the first fifty positive even numbers by using For
loop.
The For
loop that I created is
For[natNum = 2, natNum <= 50, natNum = natNum + 2, Print[natNum]]
The output of this is a list of numbers from 2 to 50 and they are increasing by 2. Now I need these numbers to be sum so I created
Sum[For[natNum = 2, natNum <= 50, natNum = natNum + 2, Print[natNum]]]
However, it is not a correct input. I am not sure if I should write the Sum
inside the For
loop.
homework
$endgroup$
I am requested to do a sum of the first fifty positive even numbers by using For
loop.
The For
loop that I created is
For[natNum = 2, natNum <= 50, natNum = natNum + 2, Print[natNum]]
The output of this is a list of numbers from 2 to 50 and they are increasing by 2. Now I need these numbers to be sum so I created
Sum[For[natNum = 2, natNum <= 50, natNum = natNum + 2, Print[natNum]]]
However, it is not a correct input. I am not sure if I should write the Sum
inside the For
loop.
homework
homework
edited 1 hour ago
MarcoB
36.6k556112
36.6k556112
asked 4 hours ago
Laura FigueroaLaura Figueroa
61
61
3
$begingroup$
If this is a class assignment, I'd suggest withdrawing from the class.For
loops are almost never a good way to do anything in Mathematica.
$endgroup$
– John Doty
3 hours ago
$begingroup$
If you want the first 50 positive even numbers, I believe that is {2, 4, ..., 100}. The sum is (2+100) + (4+98) + ... + (50 + 52) = 102 * 25 = 2550.
$endgroup$
– mjw
2 hours ago
$begingroup$
Total@Range[2, 2*50, 2]
would be pretty direct. Note also thatPrint
prints its arguments, but does not return them (in fact, it returnsNull
).
$endgroup$
– MarcoB
1 hour ago
2
$begingroup$
Since the days of Carl Friedrich Gauß we know that using aFor
loop to compute50 * 51
is a pretty bad idea....
$endgroup$
– Henrik Schumacher
35 mins ago
add a comment |
3
$begingroup$
If this is a class assignment, I'd suggest withdrawing from the class.For
loops are almost never a good way to do anything in Mathematica.
$endgroup$
– John Doty
3 hours ago
$begingroup$
If you want the first 50 positive even numbers, I believe that is {2, 4, ..., 100}. The sum is (2+100) + (4+98) + ... + (50 + 52) = 102 * 25 = 2550.
$endgroup$
– mjw
2 hours ago
$begingroup$
Total@Range[2, 2*50, 2]
would be pretty direct. Note also thatPrint
prints its arguments, but does not return them (in fact, it returnsNull
).
$endgroup$
– MarcoB
1 hour ago
2
$begingroup$
Since the days of Carl Friedrich Gauß we know that using aFor
loop to compute50 * 51
is a pretty bad idea....
$endgroup$
– Henrik Schumacher
35 mins ago
3
3
$begingroup$
If this is a class assignment, I'd suggest withdrawing from the class.
For
loops are almost never a good way to do anything in Mathematica.$endgroup$
– John Doty
3 hours ago
$begingroup$
If this is a class assignment, I'd suggest withdrawing from the class.
For
loops are almost never a good way to do anything in Mathematica.$endgroup$
– John Doty
3 hours ago
$begingroup$
If you want the first 50 positive even numbers, I believe that is {2, 4, ..., 100}. The sum is (2+100) + (4+98) + ... + (50 + 52) = 102 * 25 = 2550.
$endgroup$
– mjw
2 hours ago
$begingroup$
If you want the first 50 positive even numbers, I believe that is {2, 4, ..., 100}. The sum is (2+100) + (4+98) + ... + (50 + 52) = 102 * 25 = 2550.
$endgroup$
– mjw
2 hours ago
$begingroup$
Total@Range[2, 2*50, 2]
would be pretty direct. Note also that Print
prints its arguments, but does not return them (in fact, it returns Null
).$endgroup$
– MarcoB
1 hour ago
$begingroup$
Total@Range[2, 2*50, 2]
would be pretty direct. Note also that Print
prints its arguments, but does not return them (in fact, it returns Null
).$endgroup$
– MarcoB
1 hour ago
2
2
$begingroup$
Since the days of Carl Friedrich Gauß we know that using a
For
loop to compute 50 * 51
is a pretty bad idea....$endgroup$
– Henrik Schumacher
35 mins ago
$begingroup$
Since the days of Carl Friedrich Gauß we know that using a
For
loop to compute 50 * 51
is a pretty bad idea....$endgroup$
– Henrik Schumacher
35 mins ago
add a comment |
2 Answers
2
active
oldest
votes
$begingroup$
Anyone asking you to write For
loops in Mathematica for such a problem is a dolt. Nevertheless, here's how you might do that:
rslt = 0;
For[i = 0, i <= 50, i += 2, rslt += i];
rslt
And here's how someone with some familiarity with Mathematica might write it
Plus @@ Range[25]*2
Now, spend the time you were going to waste writing a For
loop by reading the answers to this question Why should I avoid the For loop in Mathematica?
$endgroup$
1
$begingroup$
+1 for the first sentence.
$endgroup$
– Henrik Schumacher
37 mins ago
add a comment |
$begingroup$
The first fifty positive integers can be computed with Table
:
Q = 0; (* Initialization)
T = Table[Q + k, {k, 2 Range[50]}]
We can sum up the values of T
with Sum
:
Sum[T[[k]], {k, Range[50]}]
2550
$endgroup$
1
$begingroup$
Perhaps better / more idiomatic than yourSum
approach would be usingTotal[T]
orPlus@@T
.
$endgroup$
– MarcoB
1 hour ago
$begingroup$
Thank you! I was looking for something likeTotal
and I saw thePlus
posting above, but haven't yet learned about@@
and such. I would have thoughtMap
might work here (it does not). Anyway, yesTotal[T]
andPlus@@T
are simpler and more elegant!
$endgroup$
– mjw
3 mins ago
add a comment |
Your Answer
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
Anyone asking you to write For
loops in Mathematica for such a problem is a dolt. Nevertheless, here's how you might do that:
rslt = 0;
For[i = 0, i <= 50, i += 2, rslt += i];
rslt
And here's how someone with some familiarity with Mathematica might write it
Plus @@ Range[25]*2
Now, spend the time you were going to waste writing a For
loop by reading the answers to this question Why should I avoid the For loop in Mathematica?
$endgroup$
1
$begingroup$
+1 for the first sentence.
$endgroup$
– Henrik Schumacher
37 mins ago
add a comment |
$begingroup$
Anyone asking you to write For
loops in Mathematica for such a problem is a dolt. Nevertheless, here's how you might do that:
rslt = 0;
For[i = 0, i <= 50, i += 2, rslt += i];
rslt
And here's how someone with some familiarity with Mathematica might write it
Plus @@ Range[25]*2
Now, spend the time you were going to waste writing a For
loop by reading the answers to this question Why should I avoid the For loop in Mathematica?
$endgroup$
1
$begingroup$
+1 for the first sentence.
$endgroup$
– Henrik Schumacher
37 mins ago
add a comment |
$begingroup$
Anyone asking you to write For
loops in Mathematica for such a problem is a dolt. Nevertheless, here's how you might do that:
rslt = 0;
For[i = 0, i <= 50, i += 2, rslt += i];
rslt
And here's how someone with some familiarity with Mathematica might write it
Plus @@ Range[25]*2
Now, spend the time you were going to waste writing a For
loop by reading the answers to this question Why should I avoid the For loop in Mathematica?
$endgroup$
Anyone asking you to write For
loops in Mathematica for such a problem is a dolt. Nevertheless, here's how you might do that:
rslt = 0;
For[i = 0, i <= 50, i += 2, rslt += i];
rslt
And here's how someone with some familiarity with Mathematica might write it
Plus @@ Range[25]*2
Now, spend the time you were going to waste writing a For
loop by reading the answers to this question Why should I avoid the For loop in Mathematica?
answered 3 hours ago
High Performance MarkHigh Performance Mark
538411
538411
1
$begingroup$
+1 for the first sentence.
$endgroup$
– Henrik Schumacher
37 mins ago
add a comment |
1
$begingroup$
+1 for the first sentence.
$endgroup$
– Henrik Schumacher
37 mins ago
1
1
$begingroup$
+1 for the first sentence.
$endgroup$
– Henrik Schumacher
37 mins ago
$begingroup$
+1 for the first sentence.
$endgroup$
– Henrik Schumacher
37 mins ago
add a comment |
$begingroup$
The first fifty positive integers can be computed with Table
:
Q = 0; (* Initialization)
T = Table[Q + k, {k, 2 Range[50]}]
We can sum up the values of T
with Sum
:
Sum[T[[k]], {k, Range[50]}]
2550
$endgroup$
1
$begingroup$
Perhaps better / more idiomatic than yourSum
approach would be usingTotal[T]
orPlus@@T
.
$endgroup$
– MarcoB
1 hour ago
$begingroup$
Thank you! I was looking for something likeTotal
and I saw thePlus
posting above, but haven't yet learned about@@
and such. I would have thoughtMap
might work here (it does not). Anyway, yesTotal[T]
andPlus@@T
are simpler and more elegant!
$endgroup$
– mjw
3 mins ago
add a comment |
$begingroup$
The first fifty positive integers can be computed with Table
:
Q = 0; (* Initialization)
T = Table[Q + k, {k, 2 Range[50]}]
We can sum up the values of T
with Sum
:
Sum[T[[k]], {k, Range[50]}]
2550
$endgroup$
1
$begingroup$
Perhaps better / more idiomatic than yourSum
approach would be usingTotal[T]
orPlus@@T
.
$endgroup$
– MarcoB
1 hour ago
$begingroup$
Thank you! I was looking for something likeTotal
and I saw thePlus
posting above, but haven't yet learned about@@
and such. I would have thoughtMap
might work here (it does not). Anyway, yesTotal[T]
andPlus@@T
are simpler and more elegant!
$endgroup$
– mjw
3 mins ago
add a comment |
$begingroup$
The first fifty positive integers can be computed with Table
:
Q = 0; (* Initialization)
T = Table[Q + k, {k, 2 Range[50]}]
We can sum up the values of T
with Sum
:
Sum[T[[k]], {k, Range[50]}]
2550
$endgroup$
The first fifty positive integers can be computed with Table
:
Q = 0; (* Initialization)
T = Table[Q + k, {k, 2 Range[50]}]
We can sum up the values of T
with Sum
:
Sum[T[[k]], {k, Range[50]}]
2550
answered 2 hours ago
mjwmjw
3666
3666
1
$begingroup$
Perhaps better / more idiomatic than yourSum
approach would be usingTotal[T]
orPlus@@T
.
$endgroup$
– MarcoB
1 hour ago
$begingroup$
Thank you! I was looking for something likeTotal
and I saw thePlus
posting above, but haven't yet learned about@@
and such. I would have thoughtMap
might work here (it does not). Anyway, yesTotal[T]
andPlus@@T
are simpler and more elegant!
$endgroup$
– mjw
3 mins ago
add a comment |
1
$begingroup$
Perhaps better / more idiomatic than yourSum
approach would be usingTotal[T]
orPlus@@T
.
$endgroup$
– MarcoB
1 hour ago
$begingroup$
Thank you! I was looking for something likeTotal
and I saw thePlus
posting above, but haven't yet learned about@@
and such. I would have thoughtMap
might work here (it does not). Anyway, yesTotal[T]
andPlus@@T
are simpler and more elegant!
$endgroup$
– mjw
3 mins ago
1
1
$begingroup$
Perhaps better / more idiomatic than your
Sum
approach would be using Total[T]
or Plus@@T
.$endgroup$
– MarcoB
1 hour ago
$begingroup$
Perhaps better / more idiomatic than your
Sum
approach would be using Total[T]
or Plus@@T
.$endgroup$
– MarcoB
1 hour ago
$begingroup$
Thank you! I was looking for something like
Total
and I saw the Plus
posting above, but haven't yet learned about @@
and such. I would have thought Map
might work here (it does not). Anyway, yes Total[T]
and Plus@@T
are simpler and more elegant!$endgroup$
– mjw
3 mins ago
$begingroup$
Thank you! I was looking for something like
Total
and I saw the Plus
posting above, but haven't yet learned about @@
and such. I would have thought Map
might work here (it does not). Anyway, yes Total[T]
and Plus@@T
are simpler and more elegant!$endgroup$
– mjw
3 mins ago
add a comment |
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3
$begingroup$
If this is a class assignment, I'd suggest withdrawing from the class.
For
loops are almost never a good way to do anything in Mathematica.$endgroup$
– John Doty
3 hours ago
$begingroup$
If you want the first 50 positive even numbers, I believe that is {2, 4, ..., 100}. The sum is (2+100) + (4+98) + ... + (50 + 52) = 102 * 25 = 2550.
$endgroup$
– mjw
2 hours ago
$begingroup$
Total@Range[2, 2*50, 2]
would be pretty direct. Note also thatPrint
prints its arguments, but does not return them (in fact, it returnsNull
).$endgroup$
– MarcoB
1 hour ago
2
$begingroup$
Since the days of Carl Friedrich Gauß we know that using a
For
loop to compute50 * 51
is a pretty bad idea....$endgroup$
– Henrik Schumacher
35 mins ago