线宽小于1

Question

我想绘制这些数据

#include<iostream>

using namespace std;

struct list
{
    int data;
    list *next;
    list *prev;


};

list* createNode()
{
    list *node = new list;
    node->next = NULL;
    node->prev = NULL;
    return node;
}


void insert(list**head,int data,int position)
{
    int k = 1;
    list *current, *temp, *node = createNode();

    current = NULL;
    temp = *head;

    node->data = data;

    if (position==1)
    {
        node->next = *head;
        *head = node;
        if (*head)
        {
            (*head)->prev = node;
        }

    }
    else
    {
        while (temp->next!= NULL&&k < (position-1))
        {
            temp = temp->next;
            k++;
        }
        node->next = temp->next;
        node->prev = temp->prev;
        if (temp->next)
            temp->next->prev = node;
        temp->next= node;
    }
}
void del(list**head, int position)
{
    int k = 1;
    list *current, *temp;
    current = NULL;
    temp = *head;
    if (position == 1)
    {
        *head = (*head)->next;

        if (*head != NULL)
            (*head)->prev = NULL;
        delete temp;
        return;
    }


    while (k < position&&temp->next != NULL)
    {
        temp = temp->next;
        k++;
    }
    current = temp->prev;
    current->next = temp->next;
    if (temp->next)
        temp->next->prev = current;
    delete temp;
    return;

}
void parse(list * temp)
{



    while (temp != NULL)
    {



        cout << "->" << temp->data;
        temp = temp->next;
    }
}

void main()
{

    struct list *head = NULL;

start:                 

    int choice;


    cin >> choice;
    switch (choice)
    {
      case 1: int data, position;
              cout << "\ndata:"; cin >> data; cout << "\nposition:";
              cin>>position;
              insert(&head, data, position);
              goto start;
      case 2:parse(head);
             goto start;
      case 3:  cout << "\nposition:"; cin >> position;
               del(&head, position);
               goto start;
      default: break;
    }
    exit(0);
}

使用此代码

1   2
2   3
3   5
4   5
5   6

线宽命令似乎有效，但似乎不适用于小于1的线宽。

此图的线宽为5：

此图的线宽为1

该图的线宽为0.2

人们可能会注意到，后两个地块之间没有区别。如何强制gnuplot使用小于1的线宽？