阅读What is the L in numpy.shape and 32 in numpy.type of an array?我知道为什么＆＃34; L＆＃34;后缀是有的。但我想做一些涉及了解我的数据集大小的操作。
显然我可以做一些简单的字符串处理来摆脱后缀，但我不想假设它总是在那里（我上次运行代码时并不是这样）不同的机器）。
那么处理这个问题的pythonic方法是什么？我应该使用的是shape()而不是shape()吗？是否有一个简单的＆＃34;将数字部分转换为整数并抛弃其余部分＆＃34;我应该在输出上使用的功能？是否有某种方式告诉import Foundation
import Parse
import UIKit
extension UIImageView {
public func imageFromUrl(_ urlString: String) {
if let url = URL(string: urlString) {
let request = URLRequest(url: url)
NSURLConnection.sendAsynchronousRequest(request, queue: OperationQueue.main()) {
(response: URLResponse?, data: Data?, error: NSError?) -> Void in
if let imageData = data as Data? {
self.image = UIImage(data: imageData)
}
}
}
}
}
class offersViewController: UIViewController, UITableViewDelegate {
@IBOutlet weak var tableView: UITableView!
@IBOutlet weak var offersView: UIView!
@IBOutlet weak var offerTitleLabel: UILabel!
@IBOutlet weak var smartCode: UILabel!
@IBOutlet weak var customerName: UILabel!
@IBAction func closeButton(sender: AnyObject) {
offersView.isHidden = true
}
var array: [String] = [String]()
var arrayImages: [String] = [String]()
override func viewDidLoad(){
super.viewDidLoad()
}
override func viewDidAppear(_ animated: Bool) {
self.array.removeAll(keepingCapacity: true)
self.arrayImages.removeAll(keepingCapacity: true)
let nib = UINib(nibName: "vwTblCell", bundle: nil)
tableView.register(nib, forCellReuseIdentifier: "cell")
let date = Date()
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "EEEE"
let weekDay = dateFormatter.string(from: date)
print(weekDay)
tableView.isHidden = true
let query = PFQuery(className:"offers")
query.whereKey("day", equalTo:"\(weekDay)")
query.findObjectsInBackground {
(objects: [PFObject]?, error: NSError?) -> Void in
if error == nil {
// The find succeeded.
print("Successfully retrieved \(objects!.count) scores.")
// Do something with the found objects
if let objects = objects {
let birthdayOffer = "£25 free credit on your Birthday!"
let birthdayOfferImage = "birthday"
self.array.append(birthdayOffer as String)
print(self.array)
self.arrayImages.append(birthdayOfferImage as String)
print(self.arrayImages)
for object in objects {
let query = PFQuery(className:"offers")
query.getObjectInBackground(withId: "\(object.objectId!)"){
(gameScore: PFObject?, error: NSError?) -> Void in
if error == nil && gameScore != nil {
let offertitle = gameScore!["offertitle"] as! String
let offerImage = gameScore!["imagename"] as! String
// Add birthday to array
self.array.append(offertitle as String)
print(self.array)
self.arrayImages.append(offerImage as String)
print(self.arrayImages)
}
self.tableView.reloadData()
self.tableView.isHidden = false
}
}
}
}
}
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return array.count
}
var cell : UITableViewCell?
func tableView(_tableView: UITableView, cellForRowAtIndexPath indexPath: IndexPath) -> UITableViewCell {
let cell: TblCell = self.tableView.dequeueReusableCell(withIdentifier: "cell",for: indexPath) as! TblCell
let url = URL(string: "https://checkmyweave.co.uk/\(arrayImages[(indexPath as NSIndexPath).row]).png")
cell.offerImage.sd_setImage(with: url)
cell.offerTitleLabel.text = self.array[(indexPath as NSIndexPath).row]
let defaults = UserDefaults.standard()
let userID = defaults.string(forKey: "userID")!
let query = PFQuery(className:"members")
query.getObjectInBackground(withId: "\(userID)") {
(gameScore: PFObject?, error: NSError?) -> Void in
if error == nil && gameScore != nil {
let smartCode = gameScore!["smartcode"] as! String
let defaults = UserDefaults.standard()
let userName = defaults.string(forKey: "userName")!
self.smartCode.text = smartCode
self.customerName.text = userName
} else {
print(error)
}
}
return cell
}
func numberOfSectionsIntableView(_tableView: UITableView) -> Int {
return 1
}
private func tableView(_tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
print((indexPath as NSIndexPath).row)
let date = Date()
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "EEEE"
let weekDay = dateFormatter.string(from: date)
offerTitleLabel.text = self.array[(indexPath as NSIndexPath).row]
offersView.isHidden = false
print(offerTitleLabel.text)
let query = PFQuery(className:"offers")
query.whereKey("offertitle", equalTo:"\(offerTitleLabel.text!)")
query.whereKey("day", equalTo:"\(weekDay)")
query.findObjectsInBackground {
(objects: [PFObject]?, error: NSError?) -> Void in
if error == nil {
// The find succeeded.
print("Successfully retrieved \(objects!.count) scores.")
// Do something with the found objects
if let objects = objects {
for object in objects {
let query = PFQuery(className:"offers")
query.getObjectInBackground(withId: "\(object.objectId!)"){
(gameScore: PFObject?, error: NSError?) -> Void in
if error == nil && gameScore != nil {
let offerdesc = gameScore!["offerDesc"] as! String
print(offerdesc)
}}}}}}
}
private func tableView(_tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
return 140
}
}
我不想要后缀？
奖金问题：这是什么时候介绍/为什么它会出现在一个系统而不是另一个系统上（两个python 2.7，旧系统的numpy版本未知）？在docs中没有提及它，所以没有历史可以帮助我知道我是否可以认为新系统会有它。
答案 0 :(得分：0)
L是显示值的人工制品，表示该值存储为long，而不是int：它实际上不是部分的价值。因此，你可以忽略它。
>>> num = 123L # create a long for testing
>>> num
123L
>>> num + 1 # simple operations
124L
>>> len(range(num)) # function calls
123
>>> math.sqrt(num) # math module calls also work, most of the time.
11.090536506409418
如果你必须摆脱它，你可以使用int()：
>>> int(num) # convert to int
123
唯一可能出现问题的是你有一个非常大的值：
>>> num = 2147483648
>>> num
2147483648L
>>> range(num)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
OverflowError: range() result has too many items
虽然如果你使用range的参数那么大，那么你可能在某个地方的某个地方是unpythonic。