docs: function createWithDimensions(dims, val){
      if(!Array.isArray(dims)) throw new Error("dims must be an array.");
      if(undef(val)) throw new Error("val must be defined.");
      
      const l = dims[dims.length - 1];
      const nextDims = dims.slice(0, -1);
      const array = new Array(l).fill(val);
  
      if(nextDims.length === 0) return new Vector(array);
      return createWithDimensions(nextDims, array);
  }