Ggtcf

Pre-mixing cryogenic fuels and using only one fuel tank

Strong empirical falsification of quantum mechanics based on vacuum energy density?

Does Doodling or Improvising on the Piano Have Any Benefits?

Non-trope happy ending?

Biological Blimps: Propulsion

Does the reader need to like the PoV character?

What is the highest possible scrabble score for placing a single tile

What is going on with gets(stdin) on the site coderbyte?

Stack Interview Code methods made from class Node and Smart Pointers

How many arrows is an archer expected to fire by the end of the Tyranny of Dragons pair of adventures?

Why does this expression simplify as such?

What is the English pronunciation of "pain au chocolat"?

I found an audio circuit and I built it just fine, but I find it a bit too quiet. How do I amplify the output so that it is a bit louder?

Is it necessary to use pronouns with the verb "essere"?

What (the heck) is a Super Worm Equinox Moon?

awk assign to multiple variables at once

Has the laser at Magurele, Romania reached a tenth of the Sun's power?

Creating two special characters

Make a Bowl of Alphabet Soup

The Digit Triangles

Does the Linux kernel need a file system to run?

Is there any evidence that Cleopatra and Caesarion considered fleeing to India to escape the Romans?

Can I cause damage to electrical appliances by unplugging them when they are turned on?

Can I say "fingers" when referring to toes?

Type mismatch when passing tuple

Functions with generic parameter typesType mismatch compilation error with tupleBest approach for designing F# libraries for use from both F# and C#F# Pipelines access data from pipeline stages aboveCan a Type Provider be passed into a function as a parameterIdiomatic way in F# to establish adherence to an interface on type rather than instance levelIn F# what is the difference between float[,] and float[][] and how do I initialise float[][]?Type mismatch error in result typeElegant pattern matching on nested tuples of arbitrary lengthF# tuple, System.Tuple and collection - Type constraint mismatch?

0

The following function accepts a list, a tuple (a, b) where 'a' is a tuple of floats and a query to test against.

checkDist is a function that takes two tuples of floats and returns the distance between all points.

Now, my problem is that I run into a type missmatch error and cannot figure out why. It seems to type infer 'a' as only a single float, rather than float * float.

let intoTp lst (a, b) qry = 
 let rec intoTpLoop lst prevMax =
 match lst with
 | [] -> []
 | (feat, value) :: t ->
 let curr = checkDist feat qry // current max
 let prev = checkDist prevMax qry // prev max

 // Check to replace top
 if prev < curr then
 let nextMax = (feat, value)
 prevMax :: intoTpLoop t nextMax
 else
 (feat, value) :: intoTpLoop t prevMax

 intoTpLoop lst (a, b)

Thanks,

f#

share|improve this question

asked Mar 7 at 23:59

RazollRazoll

36115

add a comment | 

0

The following function accepts a list, a tuple (a, b) where 'a' is a tuple of floats and a query to test against.

checkDist is a function that takes two tuples of floats and returns the distance between all points.

Now, my problem is that I run into a type missmatch error and cannot figure out why. It seems to type infer 'a' as only a single float, rather than float * float.

let intoTp lst (a, b) qry = 
 let rec intoTpLoop lst prevMax =
 match lst with
 | [] -> []
 | (feat, value) :: t ->
 let curr = checkDist feat qry // current max
 let prev = checkDist prevMax qry // prev max

 // Check to replace top
 if prev < curr then
 let nextMax = (feat, value)
 prevMax :: intoTpLoop t nextMax
 else
 (feat, value) :: intoTpLoop t prevMax

 intoTpLoop lst (a, b)

Thanks,

f#

share|improve this question

asked Mar 7 at 23:59

RazollRazoll

36115

add a comment | 

The following function accepts a list, a tuple (a, b) where 'a' is a tuple of floats and a query to test against.

checkDist is a function that takes two tuples of floats and returns the distance between all points.

Now, my problem is that I run into a type missmatch error and cannot figure out why. It seems to type infer 'a' as only a single float, rather than float * float.

let intoTp lst (a, b) qry = 
 let rec intoTpLoop lst prevMax =
 match lst with
 | [] -> []
 | (feat, value) :: t ->
 let curr = checkDist feat qry // current max
 let prev = checkDist prevMax qry // prev max

 // Check to replace top
 if prev < curr then
 let nextMax = (feat, value)
 prevMax :: intoTpLoop t nextMax
 else
 (feat, value) :: intoTpLoop t prevMax

 intoTpLoop lst (a, b)

Thanks,

f#

share|improve this question

asked Mar 7 at 23:59

RazollRazoll

36115

let intoTp lst (a, b) qry = 
 let rec intoTpLoop lst prevMax =
 match lst with
 | [] -> []
 | (feat, value) :: t ->
 let curr = checkDist feat qry // current max
 let prev = checkDist prevMax qry // prev max

 // Check to replace top
 if prev < curr then
 let nextMax = (feat, value)
 prevMax :: intoTpLoop t nextMax
 else
 (feat, value) :: intoTpLoop t prevMax

 intoTpLoop lst (a, b)

share|improve this question

asked Mar 7 at 23:59

RazollRazoll

36115

share|improve this question

asked Mar 7 at 23:59

RazollRazoll

36115

asked Mar 7 at 23:59

RazollRazoll

36115

asked Mar 7 at 23:59

RazollRazoll

36115

1 Answer
1

active

oldest

votes

4

So you are calling checkDist twice, the first time you pass feat which is a single value, the second time you pass prevMax which is a tuple. There is your contradiction.

When in doubt about what is happening with the type inference it helps to add type annotations to clarify what is supposed to be what (to the inference engine, to yourself and to us).

share|improve this answer

edited Mar 8 at 0:22

answered Mar 8 at 0:09

AMieresAMieres

3,6401611

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Both feat and prevMax, when passed to checkDist, are of val float * float. feat is not a single value, it is a tuple of floats.
  
  – Razoll
  Mar 8 at 0:16
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  if feat is a tuple then prevMax :: intoTpLoop t nextMax is missing the value part
  
  – AMieres
  Mar 8 at 0:18
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  I suppose that the problem is here: | (feat, value) :: t -> It should be | feat :: t ->
  
  – AMieres
  Mar 8 at 0:24
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Yes you are right. The problem was that feat and prevMax was passed as the same type to checkDist, but then I used them differently when building the resulting list.
  
  – Razoll
  Mar 8 at 0:39
  

  
  
  
  

add a comment | 

Your Answer

StackExchange.ifUsing("editor", function ()
StackExchange.using("externalEditor", function ()
StackExchange.using("snippets", function ()
StackExchange.snippets.init();
);
);
, "code-snippets");

StackExchange.ready(function()
var channelOptions =
tags: "".split(" "),
id: "1"
;
initTagRenderer("".split(" "), "".split(" "), channelOptions);

StackExchange.using("externalEditor", function()
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled)
StackExchange.using("snippets", function()
createEditor();
);

else
createEditor();

);

function createEditor()
StackExchange.prepareEditor(
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader:
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
,
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
);



);

draft saved

draft discarded

Sign up or log in

StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);

Sign up using Google

Sign up using Facebook

Sign up using Email and Password

Post as a guest

Name

Email

Required, but never shown

StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f55054742%2ftype-mismatch-when-passing-tuple%23new-answer', 'question_page');

);

Post as a guest

Name

Email

Required, but never shown

4

So you are calling checkDist twice, the first time you pass feat which is a single value, the second time you pass prevMax which is a tuple. There is your contradiction.

When in doubt about what is happening with the type inference it helps to add type annotations to clarify what is supposed to be what (to the inference engine, to yourself and to us).

share|improve this answer

edited Mar 8 at 0:22

answered Mar 8 at 0:09

AMieresAMieres

3,6401611

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Both feat and prevMax, when passed to checkDist, are of val float * float. feat is not a single value, it is a tuple of floats.
  
  – Razoll
  Mar 8 at 0:16
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  if feat is a tuple then prevMax :: intoTpLoop t nextMax is missing the value part
  
  – AMieres
  Mar 8 at 0:18
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  I suppose that the problem is here: | (feat, value) :: t -> It should be | feat :: t ->
  
  – AMieres
  Mar 8 at 0:24
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Yes you are right. The problem was that feat and prevMax was passed as the same type to checkDist, but then I used them differently when building the resulting list.
  
  – Razoll
  Mar 8 at 0:39
  

  
  
  
  

add a comment | 

4

So you are calling checkDist twice, the first time you pass feat which is a single value, the second time you pass prevMax which is a tuple. There is your contradiction.

When in doubt about what is happening with the type inference it helps to add type annotations to clarify what is supposed to be what (to the inference engine, to yourself and to us).

share|improve this answer

edited Mar 8 at 0:22

answered Mar 8 at 0:09

AMieresAMieres

3,6401611

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Both feat and prevMax, when passed to checkDist, are of val float * float. feat is not a single value, it is a tuple of floats.
  
  – Razoll
  Mar 8 at 0:16
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  if feat is a tuple then prevMax :: intoTpLoop t nextMax is missing the value part
  
  – AMieres
  Mar 8 at 0:18
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  I suppose that the problem is here: | (feat, value) :: t -> It should be | feat :: t ->
  
  – AMieres
  Mar 8 at 0:24
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Yes you are right. The problem was that feat and prevMax was passed as the same type to checkDist, but then I used them differently when building the resulting list.
  
  – Razoll
  Mar 8 at 0:39
  

  
  
  
  

add a comment | 

So you are calling checkDist twice, the first time you pass feat which is a single value, the second time you pass prevMax which is a tuple. There is your contradiction.

When in doubt about what is happening with the type inference it helps to add type annotations to clarify what is supposed to be what (to the inference engine, to yourself and to us).

share|improve this answer

edited Mar 8 at 0:22

answered Mar 8 at 0:09

AMieresAMieres

3,6401611

share|improve this answer

edited Mar 8 at 0:22

answered Mar 8 at 0:09

AMieresAMieres

3,6401611

answered Mar 8 at 0:09

AMieresAMieres

3,6401611

answered Mar 8 at 0:09

AMieresAMieres

3,6401611